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2019-05-15Merge tag 'for-linus-5.2b-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - some minor cleanups - two small corrections for Xen on ARM - two fixes for Xen PVH guest support - a patch for a new command line option to tune virtual timer handling * tag 'for-linus-5.2b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/arm: Use p2m entry with lock protection xen/arm: Free p2m entry if fail to add it to RB tree xen/pvh: correctly setup the PV EFI interface for dom0 xen/pvh: set xen_domain_type to HVM in xen_pvh_init xenbus: drop useless LIST_HEAD in xenbus_write_watch() and xenbus_file_write() xen-netfront: mark expected switch fall-through xen: xen-pciback: fix warning Using plain integer as NULL pointer x86/xen: Add "xen_timer_slop" command line option
2019-05-14xen/privcmd-buf.c: convert to use vm_map_pages_zero()Souptick Joarder
Convert to use vm_map_pages_zero() to map range of kernel memory to user vma. This driver has ignored vm_pgoff. We could later "fix" these drivers to behave according to the normal vm_pgoff offsetting simply by removing the _zero suffix on the function name and if that causes regressions, it gives us an easy way to revert. Link: http://lkml.kernel.org/r/acf678e81d554d01a9b590716ac0ccbdcdf71c25.1552921225.git.jrdr.linux@gmail.com Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Airlie <airlied@linux.ie> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Joerg Roedel <joro@8bytes.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Cc: Pawel Osciak <pawel@osciak.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Sandy Huang <hjc@rock-chips.com> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thierry Reding <treding@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14xen/gntdev.c: convert to use vm_map_pages()Souptick Joarder
Convert to use vm_map_pages() to map range of kernel memory to user vma. map->count is passed to vm_map_pages() and internal API verify map->count against count ( count = vma_pages(vma)) for page array boundary overrun condition. Link: http://lkml.kernel.org/r/88e56e82d2db98705c2d842e9c9806c00b366d67.1552921225.git.jrdr.linux@gmail.com Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Airlie <airlied@linux.ie> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Joerg Roedel <joro@8bytes.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Cc: Pawel Osciak <pawel@osciak.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Sandy Huang <hjc@rock-chips.com> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thierry Reding <treding@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14mm/mmu_notifier: convert user range->blockable to helper functionJérôme Glisse
Use the mmu_notifier_range_blockable() helper function instead of directly dereferencing the range->blockable field. This is done to make it easier to change the mmu_notifier range field. This patch is the outcome of the following coccinelle patch: %<------------------------------------------------------------------- @@ identifier I1, FN; @@ FN(..., struct mmu_notifier_range *I1, ...) { <... -I1->blockable +mmu_notifier_range_blockable(I1) ...> } ------------------------------------------------------------------->% spatch --in-place --sp-file blockable.spatch --dir . Link: http://lkml.kernel.org/r/20190326164747.24405-3-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Cc: Christian König <christian.koenig@amd.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Ross Zwisler <zwisler@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krcmar <rkrcmar@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Christian Koenig <christian.koenig@amd.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14mm/gup: change GUP fast to use flags rather than a write 'bool'Ira Weiny
To facilitate additional options to get_user_pages_fast() change the singular write parameter to be gup_flags. This patch does not change any functionality. New functionality will follow in subsequent patches. Some of the get_user_pages_fast() call sites were unchanged because they already passed FOLL_WRITE or 0 for the write parameter. NOTE: It was suggested to change the ordering of the get_user_pages_fast() arguments to ensure that callers were converted. This breaks the current GUP call site convention of having the returned pages be the final parameter. So the suggestion was rejected. Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Mike Marshall <hubcap@omnibond.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-07Merge branch 'stable/for-linus-5.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb Pull swiotlb updates from Konrad Rzeszutek Wilk: "Cleanups in the swiotlb code and extra debugfs knobs to help with the field diagnostics" * 'stable/for-linus-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: swiotlb-xen: ensure we have a single callsite for xen_dma_map_page swiotlb-xen: simplify the DMA sync method implementations swiotlb-xen: use ->map_page to implement ->map_sg swiotlb-xen: make instances match their method names swiotlb: save io_tlb_used to local variable before leaving critical section swiotlb: dump used and total slots when swiotlb buffer is full
2019-05-07Merge tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: "Nothing major in this series, just fixes and improvements all over the map. This contains: - Series of fixes for sed-opal (David, Jonas) - Fixes and performance tweaks for BFQ (via Paolo) - Set of fixes for bcache (via Coly) - Set of fixes for md (via Song) - Enabling multi-page for passthrough requests (Ming) - Queue release fix series (Ming) - Device notification improvements (Martin) - Propagate underlying device rotational status in loop (Holger) - Removal of mtip32xx trim support, which has been disabled for years (Christoph) - Improvement and cleanup of nvme command handling (Christoph) - Add block SPDX tags (Christoph) - Cleanup/hardening of bio/bvec iteration (Christoph) - A few NVMe pull requests (Christoph) - Removal of CONFIG_LBDAF (Christoph) - Various little fixes here and there" * tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block: (164 commits) block: fix mismerge in bvec_advance block: don't drain in-progress dispatch in blk_cleanup_queue() blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release blk-mq: always free hctx after request queue is freed blk-mq: split blk_mq_alloc_and_init_hctx into two parts blk-mq: free hw queue's resource in hctx's release handler blk-mq: move cancel of requeue_work into blk_mq_release blk-mq: grab .q_usage_counter when queuing request from plug code path block: fix function name in comment nvmet: protect discovery change log event list iteration nvme: mark nvme_core_init and nvme_core_exit static nvme: move command size checks to the core nvme-fabrics: check more command sizes nvme-pci: check more command sizes nvme-pci: remove an unneeded variable initialization nvme-pci: unquiesce admin queue on shutdown nvme-pci: shutdown on timeout during deletion nvme-pci: fix psdt field for single segment sgls nvme-multipath: don't print ANA group state by default nvme-multipath: split bios with the ns_head bio_set before submitting ...
2019-05-07Merge tag 'stream_open-5.2' of https://lab.nexedi.com/kirr/linuxLinus Torvalds
Pull stream_open conversion from Kirill Smelkov: - remove unnecessary double nonseekable_open from drivers/char/dtlk.c as noticed by Pavel Machek while reviewing nonseekable_open -> stream_open mass conversion. - the mass conversion patch promised in commit 10dce8af3422 ("fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock") and is automatically generated by running $ make coccicheck MODE=patch COCCI=scripts/coccinelle/api/stream_open.cocci I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. More details on this in the patch. - finally, change VFS to pass ppos=NULL into .read/.write for files that declare themselves streams. It was suggested by Rasmus Villemoes and makes sure that if ppos starts to be erroneously used in a stream file, such bug won't go unnoticed and will produce an oops instead of creating illusion of position change being taken into account. Note: this patch does not conflict with "fuse: Add FOPEN_STREAM to use stream_open()" that will be hopefully coming via FUSE tree, because fs/fuse/ uses new-style .read_iter/.write_iter, and for these accessors position is still passed as non-pointer kiocb.ki_pos . * tag 'stream_open-5.2' of https://lab.nexedi.com/kirr/linux: vfs: pass ppos=NULL to .read()/.write() of FMODE_STREAM files *: convert stream-like files from nonseekable_open -> stream_open dtlk: remove double call to nonseekable_open
2019-05-06*: convert stream-like files from nonseekable_open -> stream_openKirill Smelkov
Using scripts/coccinelle/api/stream_open.cocci added in 10dce8af3422 ("fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock"), search and convert to stream_open all in-kernel nonseekable_open users for which read and write actually do not depend on ppos and where there is no other methods in file_operations which assume @offset access. I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. The script also does not convert files that should be valid to convert, but that currently have .llseek = noop_llseek or generic_file_llseek for unknown reason despite file being opened with nonseekable_open (e.g. drivers/input/mousedev.c) Among cases converted 14 were potentially vulnerable to read vs write deadlock (see details in 10dce8af3422): drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/infiniband/core/user_mad.c:988:1-17: ERROR: umad_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/input/misc/uinput.c:401:1-17: ERROR: uinput_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. and the rest were just safe to convert to stream_open because their read and write do not use ppos at all and corresponding file_operations do not have methods that assume @offset file access(*): arch/powerpc/platforms/52xx/mpc52xx_gpt.c:631:8-24: WARNING: mpc52xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_ibox_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_ibox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_mbox_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_mbox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_wbox_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_wbox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/um/drivers/harddog_kern.c:88:8-24: WARNING: harddog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. arch/x86/kernel/cpu/microcode/core.c:430:33-49: WARNING: microcode_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/ds1620.c:215:8-24: WARNING: ds1620_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/dtlk.c:301:1-17: WARNING: dtlk_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/ipmi/ipmi_watchdog.c:840:9-25: WARNING: ipmi_wdog_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/pcmcia/scr24x_cs.c:95:8-24: WARNING: scr24x_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/tb0219.c:246:9-25: WARNING: tb0219_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/firewire/nosy.c:306:8-24: WARNING: nosy_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/hwmon/fschmd.c:840:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/hwmon/w83793.c:1344:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/infiniband/core/ucma.c:1747:8-24: WARNING: ucma_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/infiniband/core/ucm.c:1178:8-24: WARNING: ucm_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/infiniband/core/uverbs_main.c:1086:8-24: WARNING: uverbs_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/input/joydev.c:282:1-17: WARNING: joydev_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/pci/switch/switchtec.c:393:1-17: WARNING: switchtec_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/platform/chrome/cros_ec_debugfs.c:135:8-24: WARNING: cros_ec_console_log_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/rtc/rtc-ds1374.c:470:9-25: WARNING: ds1374_wdt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/rtc/rtc-m41t80.c:805:9-25: WARNING: wdt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/s390/char/tape_char.c:293:2-18: WARNING: tape_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/s390/char/zcore.c:194:8-24: WARNING: zcore_reipl_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/s390/crypto/zcrypt_api.c:528:8-24: WARNING: zcrypt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/spi/spidev.c:594:1-17: WARNING: spidev_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/staging/pi433/pi433_if.c:974:1-17: WARNING: pi433_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/acquirewdt.c:203:8-24: WARNING: acq_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/advantechwdt.c:202:8-24: WARNING: advwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/alim1535_wdt.c:252:8-24: WARNING: ali_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/alim7101_wdt.c:217:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ar7_wdt.c:166:8-24: WARNING: ar7_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/at91rm9200_wdt.c:113:8-24: WARNING: at91wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ath79_wdt.c:135:8-24: WARNING: ath79_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/bcm63xx_wdt.c:119:8-24: WARNING: bcm63xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/cpu5wdt.c:143:8-24: WARNING: cpu5wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/cpwd.c:397:8-24: WARNING: cpwd_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/eurotechwdt.c:319:8-24: WARNING: eurwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/f71808e_wdt.c:528:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/gef_wdt.c:232:8-24: WARNING: gef_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/geodewdt.c:95:8-24: WARNING: geodewdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ib700wdt.c:241:8-24: WARNING: ibwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ibmasr.c:326:8-24: WARNING: asr_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/indydog.c:80:8-24: WARNING: indydog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/intel_scu_watchdog.c:307:8-24: WARNING: intel_scu_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/iop_wdt.c:104:8-24: WARNING: iop_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/it8712f_wdt.c:330:8-24: WARNING: it8712f_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ixp4xx_wdt.c:68:8-24: WARNING: ixp4xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ks8695_wdt.c:145:8-24: WARNING: ks8695wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/m54xx_wdt.c:88:8-24: WARNING: m54xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/machzwd.c:336:8-24: WARNING: zf_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/mixcomwd.c:153:8-24: WARNING: mixcomwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/mtx-1_wdt.c:121:8-24: WARNING: mtx1_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/mv64x60_wdt.c:136:8-24: WARNING: mv64x60_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/nuc900_wdt.c:134:8-24: WARNING: nuc900wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/nv_tco.c:164:8-24: WARNING: nv_tco_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pc87413_wdt.c:289:8-24: WARNING: pc87413_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd.c:698:8-24: WARNING: pcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd.c:737:8-24: WARNING: pcwd_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_pci.c:581:8-24: WARNING: pcipcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_pci.c:623:8-24: WARNING: pcipcwd_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_usb.c:488:8-24: WARNING: usb_pcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_usb.c:527:8-24: WARNING: usb_pcwd_temperature_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pika_wdt.c:121:8-24: WARNING: pikawdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pnx833x_wdt.c:119:8-24: WARNING: pnx833x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/rc32434_wdt.c:153:8-24: WARNING: rc32434_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/rdc321x_wdt.c:145:8-24: WARNING: rdc321x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/riowd.c:79:1-17: WARNING: riowd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sa1100_wdt.c:62:8-24: WARNING: sa1100dog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc60xxwdt.c:211:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc7240_wdt.c:139:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc8360.c:274:8-24: WARNING: sbc8360_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc_epx_c3.c:81:8-24: WARNING: epx_c3_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc_fitpc2_wdt.c:78:8-24: WARNING: fitpc2_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sb_wdog.c:108:1-17: WARNING: sbwdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sc1200wdt.c:181:8-24: WARNING: sc1200wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sc520_wdt.c:261:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sch311x_wdt.c:319:8-24: WARNING: sch311x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/scx200_wdt.c:105:8-24: WARNING: scx200_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/smsc37b787_wdt.c:369:8-24: WARNING: wb_smsc_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/w83877f_wdt.c:227:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/w83977f_wdt.c:301:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wafer5823wdt.c:200:8-24: WARNING: wafwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/watchdog_dev.c:828:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdrtas.c:379:8-24: WARNING: wdrtas_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdrtas.c:445:8-24: WARNING: wdrtas_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt285.c:104:1-17: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt977.c:276:8-24: WARNING: wdt977_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt.c:424:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt.c:484:8-24: WARNING: wdt_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt_pci.c:464:8-24: WARNING: wdtpci_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt_pci.c:527:8-24: WARNING: wdtpci_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. net/batman-adv/log.c:105:1-17: WARNING: batadv_log_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. sound/core/control.c:57:7-23: WARNING: snd_ctl_f_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. sound/core/rawmidi.c:385:7-23: WARNING: snd_rawmidi_f_ops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. sound/core/seq/seq_clientmgr.c:310:7-23: WARNING: snd_seq_f_ops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. sound/core/timer.c:1428:7-23: WARNING: snd_timer_f_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. One can also recheck/review the patch via generating it with explanation comments included via $ make coccicheck MODE=patch COCCI=scripts/coccinelle/api/stream_open.cocci SPFLAGS="-D explain" (*) This second group also contains cases with read/write deadlocks that stream_open.cocci don't yet detect, but which are still valid to convert to stream_open since ppos is not used. For example drivers/pci/switch/switchtec.c calls wait_for_completion_interruptible() in its .read, but stream_open.cocci currently detects only "wait_event*" as blocking. Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yongzhi Pan <panyongzhi@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Nikolaus Rath <Nikolaus@rath.org> Cc: Han-Wen Nienhuys <hanwen@google.com> Cc: Anatolij Gustschin <agust@denx.de> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James R. Van Zandt" <jrv@vanzandt.mv.com> Cc: Corey Minyard <minyard@acm.org> Cc: Harald Welte <laforge@gnumonks.org> Acked-by: Lubomir Rintel <lkundrak@v3.sk> [scr24x_cs] Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Johan Hovold <johan@kernel.org> Cc: David Herrmann <dh.herrmann@googlemail.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com> Cc: Jean Delvare <jdelvare@suse.com> Acked-by: Guenter Roeck <linux@roeck-us.net> [watchdog/* hwmon/*] Cc: Rudolf Marek <r.marek@assembler.cz> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Kurt Schwemmer <kurt.schwemmer@microsemi.com> Acked-by: Logan Gunthorpe <logang@deltatee.com> [drivers/pci/switch/switchtec] Acked-by: Bjorn Helgaas <bhelgaas@google.com> [drivers/pci/switch/switchtec] Cc: Benson Leung <bleung@chromium.org> Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> [platform/chrome] Cc: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> [rtc/*] Cc: Mark Brown <broonie@kernel.org> Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Zwane Mwaikambo <zwanem@gmail.com> Cc: Marek Lindner <mareklindner@neomailbox.ch> Cc: Simon Wunderlich <sw@simonwunderlich.de> Cc: Antonio Quartulli <a@unstable.cc> Cc: "David S. Miller" <davem@davemloft.net> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
2019-05-02swiotlb-xen: ensure we have a single callsite for xen_dma_map_pageChristoph Hellwig
Refactor the code a bit to make further changes easier. Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2019-05-02swiotlb-xen: simplify the DMA sync method implementationsChristoph Hellwig
Get rid of the grand multiplexer and implement the sync_single_for_cpu and sync_single_for_device methods directly, and then loop over them for the scatterlist based variants. Note that this also loses a few comments related to highlevel DMA API concepts, which have nothing to do with the swiotlb-xen implementation details. Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2019-05-02swiotlb-xen: use ->map_page to implement ->map_sgChristoph Hellwig
We can simply loop over the segments and map them, removing lots of duplicate code. Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2019-05-02swiotlb-xen: make instances match their method namesChristoph Hellwig
Just drop two pointless _attrs prefixes to make the code a little more grep-able. Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2019-04-25xenbus: drop useless LIST_HEAD in xenbus_write_watch() and xenbus_file_write()Mao Wenan
Drop LIST_HEAD where the variable it declares is never used. The declarations were introduced with the file, but the declared variables were not used. Fixes: 1107ba885e469 ("xen: add xenfs to allow usermode <-> Xen interaction") Signed-off-by: Mao Wenan <maowenan@huawei.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-04-23xen: xen-pciback: fix warning Using plain integer as NULL pointerHariprasad Kelam
Changes passing function argument 0 to NULL to avoid below sparse warning CHECK drivers/xen/xen-pciback/xenbus.c drivers/xen/xen-pciback/xenbus.c:700:51: warning: Using plain integer as NULL pointer Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-04-22Merge tag 'v5.1-rc6' into for-5.2/blockJens Axboe
Pull in v5.1-rc6 to resolve two conflicts. One is in BFQ, in just a comment, and is trivial. The other one is a conflict due to a later fix in the bio multi-page work, and needs a bit more care. * tag 'v5.1-rc6': (770 commits) Linux 5.1-rc6 block: make sure that bvec length can't be overflow block: kill all_q_node in request_queue x86/cpu/intel: Lower the "ENERGY_PERF_BIAS: Set to normal" message's log priority coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping mm/kmemleak.c: fix unused-function warning init: initialize jump labels before command line option parsing kernel/watchdog_hld.c: hard lockup message should end with a newline kcov: improve CONFIG_ARCH_HAS_KCOV help text mm: fix inactive list balancing between NUMA nodes and cgroups mm/hotplug: treat CMA pages as unmovable proc: fixup proc-pid-vm test proc: fix map_files test on F29 mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n mm/memory_hotplug: do not unlock after failing to take the device_hotplug_lock mm: swapoff: shmem_unuse() stop eviction without igrab() mm: swapoff: take notice of completion sooner mm: swapoff: remove too limiting SWAP_UNUSE_MAX_TRIES mm: swapoff: shmem_find_swap_entries() filter out other types slab: store tagged freelist for off-slab slabmgmt ... Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-17x86/irq/32: Invoke irq_ctx_init() from init_IRQ()Thomas Gleixner
irq_ctx_init() is invoked from native_init_IRQ() or from xen_init_IRQ() code. There is no reason to have this split. The interrupt stacks must be allocated no matter what. Invoke it from init_IRQ() before invoking the native or XEN init implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Josh Abraham <j.abraham1776@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20190414160146.001162606@linutronix.de
2019-04-07Merge tag 'for-linus-5.1b-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "One minor fix and a small cleanup for the xen privcmd driver" * tag 'for-linus-5.1b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Prevent buffer overflow in privcmd ioctl xen: use struct_size() helper in kzalloc()
2019-04-06fs: stream_open - opener for stream-like files so that read and write can ↵Kirill Smelkov
run simultaneously without deadlock Commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") added locking for file.f_pos access and in particular made concurrent read and write not possible - now both those functions take f_pos lock for the whole run, and so if e.g. a read is blocked waiting for data, write will deadlock waiting for that read to complete. This caused regression for stream-like files where previously read and write could run simultaneously, but after that patch could not do so anymore. See e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes to /proc/xen/xenbus") which fixes such regression for particular case of /proc/xen/xenbus. The patch that added f_pos lock in 2014 did so to guarantee POSIX thread safety for read/write/lseek and added the locking to file descriptors of all regular files. In 2014 that thread-safety problem was not new as it was already discussed earlier in 2006. However even though 2006'th version of Linus's patch was adding f_pos locking "only for files that are marked seekable with FMODE_LSEEK (thus avoiding the stream-like objects like pipes and sockets)", the 2014 version - the one that actually made it into the tree as 9c225f2655e3 - is doing so irregardless of whether a file is seekable or not. See https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/ https://lwn.net/Articles/180387 https://lwn.net/Articles/180396 for historic context. The reason that it did so is, probably, that there are many files that are marked non-seekable, but e.g. their read implementation actually depends on knowing current position to correctly handle the read. Some examples: kernel/power/user.c snapshot_read fs/debugfs/file.c u32_array_read fs/fuse/control.c fuse_conn_waiting_read + ... drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read arch/s390/hypfs/inode.c hypfs_read_iter ... Despite that, many nonseekable_open users implement read and write with pure stream semantics - they don't depend on passed ppos at all. And for those cases where read could wait for something inside, it creates a situation similar to xenbus - the write could be never made to go until read is done, and read is waiting for some, potentially external, event, for potentially unbounded time -> deadlock. Besides xenbus, there are 14 such places in the kernel that I've found with semantic patch (see below): drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write() drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write() drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write() drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write() net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write() drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write() drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write() drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write() net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write() drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write() drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write() drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write() drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write() drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write() In addition to the cases above another regression caused by f_pos locking is that now FUSE filesystems that implement open with FOPEN_NONSEEKABLE flag, can no longer implement bidirectional stream-like files - for the same reason as above e.g. read can deadlock write locking on file.f_pos in the kernel. FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f715 ("fuse: implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and write routines not depending on current position at all, and with both read and write being potentially blocking operations: See https://github.com/libfuse/osspd https://lwn.net/Articles/308445 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510 Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as "somewhat pipe-like files ..." with read handler not using offset. However that test implements only read without write and cannot exercise the deadlock scenario: https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131 https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163 https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216 I've actually hit the read vs write deadlock for real while implementing my FUSE filesystem where there is /head/watch file, for which open creates separate bidirectional socket-like stream in between filesystem and its user with both read and write being later performed simultaneously. And there it is semantically not easy to split the stream into two separate read-only and write-only channels: https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169 Let's fix this regression. The plan is: 1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS - doing so would break many in-kernel nonseekable_open users which actually use ppos in read/write handlers. 2. Add stream_open() to kernel to open stream-like non-seekable file descriptors. Read and write on such file descriptors would never use nor change ppos. And with that property on stream-like files read and write will be running without taking f_pos lock - i.e. read and write could be running simultaneously. 3. With semantic patch search and convert to stream_open all in-kernel nonseekable_open users for which read and write actually do not depend on ppos and where there is no other methods in file_operations which assume @offset access. 4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via steam_open if that bit is present in filesystem open reply. It was tempting to change fs/fuse/ open handler to use stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE, and in particular GVFS which actually uses offset in its read and write handlers https://codesearch.debian.net/search?q=-%3Enonseekable+%3D https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481 so if we would do such a change it will break a real user. 5. Add stream_open and FOPEN_STREAM handling to stable kernels starting from v3.14+ (the kernel where 9c225f2655 first appeared). This will allow to patch OSSPD and other FUSE filesystems that provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE in their open handler and this way avoid the deadlock on all kernel versions. This should work because fs/fuse/ ignores unknown open flags returned from a filesystem and so passing FOPEN_STREAM to a kernel that is not aware of this flag cannot hurt. In turn the kernel that is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE is sufficient to implement streams without read vs write deadlock. This patch adds stream_open, converts /proc/xen/xenbus to it and adds semantic patch to automatically locate in-kernel places that are either required to be converted due to read vs write deadlock, or that are just safe to be converted because read and write do not use ppos and there are no other funky methods in file_operations. Regarding semantic patch I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. The script also does not convert files that should be valid to convert, but that currently have .llseek = noop_llseek or generic_file_llseek for unknown reason despite file being opened with nonseekable_open (e.g. drivers/input/mousedev.c) Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yongzhi Pan <panyongzhi@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Nikolaus Rath <Nikolaus@rath.org> Cc: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-04-05xen: use struct_size() helper in kzalloc()Andrea Righi
struct privcmd_buf_vma_private has a zero-sized array at the end (pages), use the new struct_size() helper to determine the proper allocation size and avoid potential type mistakes. Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-04-01block: pass page to xen_biovec_phys_mergeableMing Lei
xen_biovec_phys_mergeable() only needs .bv_page of the 2nd bio bvec for checking if the two bvecs can be merged, so pass page to xen_biovec_phys_mergeable() directly. No function change. Cc: ris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: xen-devel@lists.xenproject.org Cc: Omar Sandoval <osandov@fb.com> Cc: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-03-15xen/balloon: Fix mapping PG_offline pages to user spaceDavid Hildenbrand
The XEN balloon driver - in contrast to other balloon drivers - allows to map some inflated pages to user space. Such pages are allocated via alloc_xenballooned_pages() and freed via free_xenballooned_pages(). The pfn space of these allocated pages is used to map other things by the hypervisor using hypercalls. Pages marked with PG_offline must never be mapped to user space (as this page type uses the mapcount field of struct pages). So what we can do is, clear/set PG_offline when allocating/freeing an inflated pages. This way, most inflated pages can be excluded by dumping tools and the "reused for other purpose" balloon pages are correctly not marked as PG_offline. Fixes: 77c4adf6a6df (xen/balloon: mark inflated pages PG_offline) Reported-by: Julien Grall <julien.grall@arm.com> Tested-by: Julien Grall <julien.grall@arm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-03-12Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: - a few misc things - the rest of MM - remove flex_arrays, replace with new simple radix-tree implementation * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (38 commits) Drop flex_arrays sctp: convert to genradix proc: commit to genradix generic radix trees selinux: convert to kvmalloc md: convert to kvmalloc openvswitch: convert to kvmalloc of: fix kmemleak crash caused by imbalance in early memory reservation mm: memblock: update comments and kernel-doc memblock: split checks whether a region should be skipped to a helper function memblock: remove memblock_{set,clear}_region_flags memblock: drop memblock_alloc_*_nopanic() variants memblock: memblock_alloc_try_nid: don't panic treewide: add checks for the return value of memblock_alloc*() swiotlb: add checks for the return value of memblock_alloc*() init/main: add checks for the return value of memblock_alloc*() mm/percpu: add checks for the return value of memblock_alloc*() sparc: add checks for the return value of memblock_alloc*() ia64: add checks for the return value of memblock_alloc*() arch: don't memset(0) memory returned by memblock_alloc() ...
2019-03-12treewide: add checks for the return value of memblock_alloc*()Mike Rapoport
Add check for the return value of memblock_alloc*() functions and call panic() in case of error. The panic message repeats the one used by panicing memblock allocators with adjustment of parameters to include only relevant ones. The replacement was mostly automated with semantic patches like the one below with manual massaging of format strings. @@ expression ptr, size, align; @@ ptr = memblock_alloc(size, align); + if (!ptr) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align); [anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type] Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org [rppt@linux.ibm.com: fix format strings for panics after memblock_alloc] Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com [rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails] Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx [akpm@linux-foundation.org: fix xtensa printk warning] Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Reviewed-by: Guo Ren <ren_guo@c-sky.com> [c-sky] Acked-by: Paul Burton <paul.burton@mips.com> [MIPS] Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390] Reviewed-by: Juergen Gross <jgross@suse.com> [Xen] Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa] Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dennis Zhou <dennis@kernel.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-11Merge tag 'for-linus-5.1a-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: "xen fixes and features: - remove fallback code for very old Xen hypervisors - three patches for fixing Xen dom0 boot regressions - an old patch for Xen PCI passthrough which was never applied for unknown reasons - some more minor fixes and cleanup patches" * tag 'for-linus-5.1a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: fix dom0 boot on huge systems xen, cpu_hotplug: Prevent an out of bounds access xen: remove pre-xen3 fallback handlers xen/ACPI: Switch to bitmap_zalloc() x86/xen: dont add memory above max allowed allocation x86: respect memory size limiting via mem= parameter xen/gntdev: Check and release imported dma-bufs on close xen/gntdev: Do not destroy context while dma-bufs are in use xen/pciback: Don't disable PCI_COMMAND on PCI device reset. xen-scsiback: mark expected switch fall-through xen: mark expected switch fall-through
2019-03-09Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull SCSI updates from James Bottomley: "This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc, hisi_sas, target/iscsi and target/core. Additionally Christoph refactored gdth as part of the dma changes. The major mid-layer change this time is the removal of bidi commands and with them the whole of the osd/exofs driver and filesystem. This is a major simplification for block and mq in particular" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (240 commits) scsi: cxgb4i: validate tcp sequence number only if chip version <= T5 scsi: cxgb4i: get pf number from lldi->pf scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c scsi: mpt3sas: Add missing breaks in switch statements scsi: aacraid: Fix missing break in switch statement scsi: kill command serial number scsi: csiostor: drop serial_number usage scsi: mvumi: use request tag instead of serial_number scsi: dpt_i2o: remove serial number usage scsi: st: osst: Remove negative constant left-shifts scsi: ufs-bsg: Allow reading descriptors scsi: ufs: Allow reading descriptor via raw upiu scsi: ufs-bsg: Change the calling convention for write descriptor scsi: ufs: Remove unused device quirks Revert "scsi: ufs: disable vccq if it's not needed by UFS device" scsi: megaraid_sas: Remove a bunch of set but not used variables scsi: clean obsolete return values of eh_timed_out scsi: sd: Optimal I/O size should be a multiple of physical block size scsi: MAINTAINERS: SCSI initiator and target tweaks scsi: fcoe: make use of fip_mode enum complete ...
2019-03-08xen, cpu_hotplug: Prevent an out of bounds accessDan Carpenter
The "cpu" variable comes from the sscanf() so Smatch marks it as untrusted data. We can't pass a higher value than "nr_cpu_ids" to cpu_possible() or it results in an out of bounds access. Fixes: d68d82afd4c8 ("xen: implement CPU hotplugging") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-03-05xen/balloon: mark inflated pages PG_offlineDavid Hildenbrand
Mark inflated and never onlined pages PG_offline, to tell the world that the content is stale and should not be dumped. Link: http://lkml.kernel.org/r/20181119101616.8901-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Hansen <chansen3@cisco.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Julien Freche <jfreche@vmware.com> Cc: Kairui Song <kasong@redhat.com> Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <len.brown@intel.com> Cc: Lianbo Jiang <lijiang@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Nadav Amit <namit@vmware.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Pankaj gupta <pagupta@redhat.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xavier Deguillard <xdeguillard@vmware.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05mm/page_alloc.c: memory hotplug: free pages as higher orderArun KS
When freeing pages are done with higher order, time spent on coalescing pages by buddy allocator can be reduced. With section size of 256MB, hot add latency of a single section shows improvement from 50-60 ms to less than 1 ms, hence improving the hot add latency by 60 times. Modify external providers of online callback to align with the change. [arunks@codeaurora.org: v11] Link: http://lkml.kernel.org/r/1547792588-18032-1-git-send-email-arunks@codeaurora.org [akpm@linux-foundation.org: remove unused local, per Arun] [akpm@linux-foundation.org: avoid return of void-returning __free_pages_core(), per Oscar] [akpm@linux-foundation.org: fix it for mm-convert-totalram_pages-and-totalhigh_pages-variables-to-atomic.patch] [arunks@codeaurora.org: v8] Link: http://lkml.kernel.org/r/1547032395-24582-1-git-send-email-arunks@codeaurora.org [arunks@codeaurora.org: v9] Link: http://lkml.kernel.org/r/1547098543-26452-1-git-send-email-arunks@codeaurora.org Link: http://lkml.kernel.org/r/1538727006-5727-1-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mathieu Malaterre <malat@debian.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Souptick Joarder <jrdr.linux@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Srivatsa Vaddagiri <vatsa@codeaurora.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05xen: remove pre-xen3 fallback handlersArnd Bergmann
The legacy hypercall handlers were originally added with a comment explaining that "copying the argument structures in HYPERVISOR_event_channel_op() and HYPERVISOR_physdev_op() into the local variable is sufficiently safe" and only made sure to not write past the end of the argument structure, the checks in linux/string.h disagree with that, when link-time optimizations are used: In function 'memcpy', inlined from 'pirq_query_unmask' at drivers/xen/fallback.c:53:2, inlined from '__startup_pirq' at drivers/xen/events/events_base.c:529:2, inlined from 'restore_pirqs' at drivers/xen/events/events_base.c:1439:3, inlined from 'xen_irq_resume' at drivers/xen/events/events_base.c:1581:2: include/linux/string.h:350:3: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter __read_overflow2(); ^ Further research turned out that only Xen 3.0.2 or earlier required the fallback at all, while all versions in use today don't need it. As far as I can tell, it is not even possible to run a mainline kernel on those old Xen releases, at the time when they were in use, only a patched kernel was supported anyway. Fixes: cf47a83fb06e ("xen/hypercall: fix hypercall fallback code for very old hypervisors") Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Jan Beulich <JBeulich@suse.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-03-04xen/ACPI: Switch to bitmap_zalloc()Andy Shevchenko
Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type instead of opaque void *. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18x86/xen: dont add memory above max allowed allocationJuergen Gross
Don't allow memory to be added above the allowed maximum allocation limit set by Xen. Trying to do so would result in cases like the following: [ 584.559652] ------------[ cut here ]------------ [ 584.564897] WARNING: CPU: 2 PID: 1 at ../arch/x86/xen/multicalls.c:129 xen_alloc_pte+0x1c7/0x390() [ 584.575151] Modules linked in: [ 584.578643] Supported: Yes [ 584.581750] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.4.120-92.70-default #1 [ 584.590000] Hardware name: Cisco Systems Inc UCSC-C460-M4/UCSC-C460-M4, BIOS C460M4.4.0.1b.0.0629181419 06/29/2018 [ 584.601862] 0000000000000000 ffffffff813175a0 0000000000000000 ffffffff8184777c [ 584.610200] ffffffff8107f4e1 ffff880487eb7000 ffff8801862b79c0 ffff88048608d290 [ 584.618537] 0000000000487eb7 ffffea0000000201 ffffffff81009de7 ffffffff81068561 [ 584.626876] Call Trace: [ 584.629699] [<ffffffff81019ad9>] dump_trace+0x59/0x340 [ 584.635645] [<ffffffff81019eaa>] show_stack_log_lvl+0xea/0x170 [ 584.642391] [<ffffffff8101ac51>] show_stack+0x21/0x40 [ 584.648238] [<ffffffff813175a0>] dump_stack+0x5c/0x7c [ 584.654085] [<ffffffff8107f4e1>] warn_slowpath_common+0x81/0xb0 [ 584.660932] [<ffffffff81009de7>] xen_alloc_pte+0x1c7/0x390 [ 584.667289] [<ffffffff810647f0>] pmd_populate_kernel.constprop.6+0x40/0x80 [ 584.675241] [<ffffffff815ecfe8>] phys_pmd_init+0x210/0x255 [ 584.681587] [<ffffffff815ed207>] phys_pud_init+0x1da/0x247 [ 584.687931] [<ffffffff815edb3b>] kernel_physical_mapping_init+0xf5/0x1d4 [ 584.695682] [<ffffffff815e9bdd>] init_memory_mapping+0x18d/0x380 [ 584.702631] [<ffffffff81064699>] arch_add_memory+0x59/0xf0 Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18xen/gntdev: Check and release imported dma-bufs on closeOleksandr Andrushchenko
Check if there are any imported dma-bufs left not released by user-space when grant device's release callback is called and free those if this is the case. This can happen if user-space leaks the buffers because of a bug or application has been terminated for any reason. Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Reviewed-by: Boris Ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18xen/gntdev: Do not destroy context while dma-bufs are in useOleksandr Andrushchenko
If there are exported DMA buffers which are still in use and grant device is closed by either normal user-space close or by a signal this leads to the grant device context to be destroyed, thus making it not possible to correctly destroy those exported buffers when they are returned back to gntdev and makes the module crash: [ 339.617540] [<ffff00000854c0d8>] dmabuf_exp_ops_release+0x40/0xa8 [ 339.617560] [<ffff00000867a6e8>] dma_buf_release+0x60/0x190 [ 339.617577] [<ffff0000082211f0>] __fput+0x88/0x1d0 [ 339.617589] [<ffff000008221394>] ____fput+0xc/0x18 [ 339.617607] [<ffff0000080ed4e4>] task_work_run+0x9c/0xc0 [ 339.617622] [<ffff000008089714>] do_notify_resume+0xfc/0x108 Fix this by referencing gntdev on each DMA buffer export and unreferencing on buffer release. Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Reviewed-by: Boris Ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18xen/pciback: Don't disable PCI_COMMAND on PCI device reset.Konrad Rzeszutek Wilk
There is no need for this at all. Worst it means that if the guest tries to write to BARs it could lead (on certain platforms) to PCI SERR errors. Please note that with af6fc858a35b90e89ea7a7ee58e66628c55c776b "xen-pciback: limit guest control of command register" a guest is still allowed to enable those control bits (safely), but is not allowed to disable them and that therefore a well behaved frontend which enables things before using them will still function correctly. This is done via an write to the configuration register 0x4 which triggers on the backend side: command_write \- pci_enable_device \- pci_enable_device_flags \- do_pci_enable_device \- pcibios_enable_device \-pci_enable_resourcess [which enables the PCI_COMMAND_MEMORY|PCI_COMMAND_IO] However guests (and drivers) which don't do this could cause problems, including the security issues which XSA-120 sought to address. Reported-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18xen-scsiback: mark expected switch fall-throughGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warning: drivers/xen/xen-scsiback.c: In function ‘scsiback_frontend_changed’: drivers/xen/xen-scsiback.c:1185:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (xenbus_dev_is_online(dev)) ^ drivers/xen/xen-scsiback.c:1188:2: note: here case XenbusStateUnknown: ^~~~ Warning level 3 was used: -Wimplicit-fallthrough=3 Notice that, in this particular case, the code comment is modified in accordance with what GCC is expecting to find. This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18xen: mark expected switch fall-throughGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warning: drivers/xen/xen-pciback/xenbus.c: In function ‘xen_pcibk_frontend_changed’: drivers/xen/xen-pciback/xenbus.c:545:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (xenbus_dev_is_online(xdev)) ^ drivers/xen/xen-pciback/xenbus.c:548:2: note: here case XenbusStateUnknown: ^~~~ Warning level 3 was used: -Wimplicit-fallthrough=3 Notice that, in this particular case, the code comment is modified in accordance with what GCC is expecting to find. This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-04scsi: target/core: Remove the write_pending_status() callback functionBart Van Assche
Due to the patch that makes TMF handling synchronous the write_pending_status() callback function is no longer called. Hence remove it. Acked-by: Felipe Balbi <balbi@ti.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Reviewed-by: Andy Grover <agrover@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Cc: Nicholas Bellinger <nab@linux-iscsi.org> Cc: Mike Christie <mchristi@redhat.com> Cc: Himanshu Madhani <himanshu.madhani@qlogic.com> Cc: Quinn Tran <quinn.tran@qlogic.com> Cc: Saurav Kashyap <saurav.kashyap@qlogic.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Juergen Gross <jgross@suse.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-01-23arm64/xen: fix xen-swiotlb cache flushingChristoph Hellwig
Xen-swiotlb hooks into the arm/arm64 arch code through a copy of the DMA DMA mapping operations stored in the struct device arch data. Switching arm64 to use the direct calls for the merged DMA direct / swiotlb code broke this scheme. Replace the indirect calls with direct-calls in xen-swiotlb as well to fix this problem. Fixes: 356da6d0cde3 ("dma-mapping: bypass indirect calls for dma-direct") Reported-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-01-19Merge tag 'for-linus-5.0-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - Several fixes for the Xen pvcalls drivers (1 fix for the backend and 8 for the frontend). - A fix for a rather longstanding bug in the Xen sched_clock() interface which led to weird time jumps when migrating the system. - A fix for avoiding accesses to x2apic MSRs in Xen PV guests. * tag 'for-linus-5.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Fix x86 sched_clock() interface for xen pvcalls-front: fix potential null dereference always clear the X2APIC_ENABLE bit for PV guest pvcalls-front: Avoid get_free_pages(GFP_KERNEL) under spinlock xen/pvcalls: remove set but not used variable 'intf' pvcalls-back: set -ENOTCONN in pvcalls_conn_back_read pvcalls-front: don't return error when the ring is full pvcalls-front: properly allocate sk pvcalls-front: don't try to free unallocated rings pvcalls-front: read all data before closing the connection
2019-01-16xen: Fix x86 sched_clock() interface for xenJuergen Gross
Commit f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface") broke Xen guest time handling across migration: [ 187.249951] Freezing user space processes ... (elapsed 0.001 seconds) done. [ 187.251137] OOM killer disabled. [ 187.251137] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. [ 187.252299] suspending xenstore... [ 187.266987] xen:grant_table: Grant tables using version 1 layout [18446743811.706476] OOM killer enabled. [18446743811.706478] Restarting tasks ... done. [18446743811.720505] Setting capacity to 16777216 Fix that by setting xen_sched_clock_offset at resume time to ensure a monotonic clock value. [boris: replaced pr_info() with pr_info_once() in xen_callback_vector() to avoid printing with incorrect timestamp during resume (as we haven't re-adjusted the clock yet)] Fixes: f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface") Cc: <stable@vger.kernel.org> # 4.11 Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-15pvcalls-front: fix potential null dereferenceWen Yang
static checker warning: drivers/xen/pvcalls-front.c:373 alloc_active_ring() error: we previously assumed 'map->active.ring' could be null (see line 357) drivers/xen/pvcalls-front.c 351 static int alloc_active_ring(struct sock_mapping *map) 352 { 353 void *bytes; 354 355 map->active.ring = (struct pvcalls_data_intf *) 356 get_zeroed_page(GFP_KERNEL); 357 if (!map->active.ring) ^^^^^^^^^^^^^^^^^ Check 358 goto out; 359 360 map->active.ring->ring_order = PVCALLS_RING_ORDER; 361 bytes = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 362 PVCALLS_RING_ORDER); 363 if (!bytes) 364 goto out; 365 366 map->active.data.in = bytes; 367 map->active.data.out = bytes + 368 XEN_FLEX_RING_SIZE(PVCALLS_RING_ORDER); 369 370 return 0; 371 372 out: --> 373 free_active_ring(map); ^^^ Add null check on map->active.ring before dereferencing it to avoid any NULL pointer dereferences. Fixes: 9f51c05dc41a ("pvcalls-front: Avoid get_free_pages(GFP_KERNEL) under spinlock") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Suggested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> CC: Boris Ostrovsky <boris.ostrovsky@oracle.com> CC: Juergen Gross <jgross@suse.com> CC: Stefano Stabellini <sstabellini@kernel.org> CC: Dan Carpenter <dan.carpenter@oracle.com> CC: xen-devel@lists.xenproject.org CC: linux-kernel@vger.kernel.org Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-10pvcalls-front: Avoid get_free_pages(GFP_KERNEL) under spinlockWen Yang
The problem is that we call this with a spin lock held. The call tree is: pvcalls_front_accept() holds bedata->socket_lock. -> create_active() -> __get_free_pages() uses GFP_KERNEL The create_active() function is only called from pvcalls_front_accept() with a spin_lock held, The allocation is not allowed to sleep and GFP_KERNEL is not sufficient. This issue was detected by using the Coccinelle software. v2: Add a function doing the allocations which is called outside the lock and passing the allocated data to create_active(). v3: Use the matching deallocators i.e., free_page() and free_pages(), respectively. v4: It would be better to pre-populate map (struct sock_mapping), rather than introducing one more new struct. v5: Since allocating the data outside of this call it should also be freed outside, when create_active() fails. Move kzalloc(sizeof(*map2), GFP_ATOMIC) outside spinlock and use GFP_KERNEL instead. v6: Drop the superfluous calls. Suggested-by: Juergen Gross <jgross@suse.com> Suggested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Suggested-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Acked-by: Stefano Stabellini <sstabellini@kernel.org> CC: Julia Lawall <julia.lawall@lip6.fr> CC: Boris Ostrovsky <boris.ostrovsky@oracle.com> CC: Juergen Gross <jgross@suse.com> CC: Stefano Stabellini <sstabellini@kernel.org> CC: xen-devel@lists.xenproject.org CC: linux-kernel@vger.kernel.org Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-04xen/pvcalls: remove set but not used variable 'intf'YueHaibing
Fixes gcc '-Wunused-but-set-variable' warning: drivers/xen/pvcalls-back.c: In function 'pvcalls_sk_state_change': drivers/xen/pvcalls-back.c:286:28: warning: variable 'intf' set but not used [-Wunused-but-set-variable] It not used since e6587cdbd732 ("pvcalls-back: set -ENOTCONN in pvcalls_conn_back_read") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-03Remove 'type' argument from access_ok() functionLinus Torvalds
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-02pvcalls-back: set -ENOTCONN in pvcalls_conn_back_readStefano Stabellini
When a connection is closing we receive on pvcalls_sk_state_change notification. Instead of setting the connection as closed immediately (-ENOTCONN), let's read one more time from it: pvcalls_conn_back_read will set the connection as closed when necessary. That way, we avoid races between pvcalls_sk_state_change and pvcalls_back_ioworker. Signed-off-by: Stefano Stabellini <stefanos@xilinx.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-02pvcalls-front: don't return error when the ring is fullStefano Stabellini
When the ring is full, size == array_size. It is not an error condition, so simply return 0 instead of an error. Signed-off-by: Stefano Stabellini <stefanos@xilinx.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-02pvcalls-front: properly allocate skStefano Stabellini
Don't use kzalloc: it ends up leaving sk->sk_prot not properly initialized. Use sk_alloc instead and define our own trivial struct proto. Signed-off-by: Stefano Stabellini <stefanos@xilinx.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-02pvcalls-front: don't try to free unallocated ringsStefano Stabellini
inflight_req_id is 0 when initialized. If inflight_req_id is 0, there is no accept_map to free. Fix the check in pvcalls_front_release. Signed-off-by: Stefano Stabellini <stefanos@xilinx.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-01-02pvcalls-front: read all data before closing the connectionStefano Stabellini
When a connection is closing in_error is set to ENOTCONN. There could still be outstanding data on the ring left by the backend. Before closing the connection on the frontend side, drain the ring. Signed-off-by: Stefano Stabellini <stefanos@xilinx.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>