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2020-04-07mm: adjust shuffle code to allow for future coalescingAlexander Duyck
Patch series "mm / virtio: Provide support for free page reporting", v17. This series provides an asynchronous means of reporting free guest pages to a hypervisor so that the memory associated with those pages can be dropped and reused by other processes and/or guests on the host. Using this it is possible to avoid unnecessary I/O to disk and greatly improve performance in the case of memory overcommit on the host. When enabled we will be performing a scan of free memory every 2 seconds while pages of sufficiently high order are being freed. In each pass at least one sixteenth of each free list will be reported. By doing this we avoid racing against other threads that may be causing a high amount of memory churn. The lowest page order currently scanned when reporting pages is pageblock_order so that this feature will not interfere with the use of Transparent Huge Pages in the case of virtualization. Currently this is only in use by virtio-balloon however there is the hope that at some point in the future other hypervisors might be able to make use of it. In the virtio-balloon/QEMU implementation the hypervisor is currently using MADV_DONTNEED to indicate to the host kernel that the page is currently free. It will be zeroed and faulted back into the guest the next time the page is accessed. To track if a page is reported or not the Uptodate flag was repurposed and used as a Reported flag for Buddy pages. We walk though the free list isolating pages and adding them to the scatterlist until we either encounter the end of the list or have processed at least one sixteenth of the pages that were listed in nr_free prior to us starting. If we fill the scatterlist before we reach the end of the list we rotate the list so that the first unreported page we encounter is moved to the head of the list as that is where we will resume after we have freed the reported pages back into the tail of the list. Below are the results from various benchmarks. I primarily focused on two tests. The first is the will-it-scale/page_fault2 test, and the other is a modified version of will-it-scale/page_fault1 that was enabled to use THP. I did this as it allows for better visibility into different parts of the memory subsystem. The guest is running with 32G for RAM on one node of a E5-2630 v3. The host has had some features such as CPU turbo disabled in the BIOS. Test page_fault1 (THP) page_fault2 Name tasks Process Iter STDEV Process Iter STDEV Baseline 1 1012402.50 0.14% 361855.25 0.81% 16 8827457.25 0.09% 3282347.00 0.34% Patches Applied 1 1007897.00 0.23% 361887.00 0.26% 16 8784741.75 0.39% 3240669.25 0.48% Patches Enabled 1 1010227.50 0.39% 359749.25 0.56% 16 8756219.00 0.24% 3226608.75 0.97% Patches Enabled 1 1050982.00 4.26% 357966.25 0.14% page shuffle 16 8672601.25 0.49% 3223177.75 0.40% Patches enabled 1 1003238.00 0.22% 360211.00 0.22% shuffle w/ RFC 16 8767010.50 0.32% 3199874.00 0.71% The results above are for a baseline with a linux-next-20191219 kernel, that kernel with this patch set applied but page reporting disabled in virtio-balloon, the patches applied and page reporting fully enabled, the patches enabled with page shuffling enabled, and the patches applied with page shuffling enabled and an RFC patch that makes used of MADV_FREE in QEMU. These results include the deviation seen between the average value reported here versus the high and/or low value. I observed that during the test memory usage for the first three tests never dropped whereas with the patches fully enabled the VM would drop to using only a few GB of the host's memory when switching from memhog to page fault tests. Any of the overhead visible with this patch set enabled seems due to page faults caused by accessing the reported pages and the host zeroing the page before giving it back to the guest. This overhead is much more visible when using THP than with standard 4K pages. In addition page shuffling seemed to increase the amount of faults generated due to an increase in memory churn. The overehad is reduced when using MADV_FREE as we can avoid the extra zeroing of the pages when they are reintroduced to the host, as can be seen when the RFC is applied with shuffling enabled. The overall guest size is kept fairly small to only a few GB while the test is running. If the host memory were oversubscribed this patch set should result in a performance improvement as swapping memory in the host can be avoided. A brief history on the background of free page reporting can be found at: https://lore.kernel.org/lkml/29f43d5796feed0dec8e8bb98b187d9dac03b900.camel@linux.intel.com/ This patch (of 9): Move the head/tail adding logic out of the shuffle code and into the __free_one_page function since ultimately that is where it is really needed anyway. By doing this we should be able to reduce the overhead and can consolidate all of the list addition bits in one spot. Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: David Hildenbrand <david@redhat.com> Cc: Yang Zhang <yang.zhang.wz@gmail.com> Cc: Pankaj Gupta <pagupta@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Wei Wang <wei.w.wang@intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: wei qi <weiqi4@huawei.com> Link: http://lkml.kernel.org/r/20200211224602.29318.84523.stgit@localhost.localdomain Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm: code cleanup for MADV_FREEHuang Ying
Some comments for MADV_FREE is revised and added to help people understand the MADV_FREE code, especially the page flag, PG_swapbacked. This makes page_is_file_cache() isn't consistent with its comments. So the function is renamed to page_is_file_lru() to make them consistent again. All these are put in one patch as one logical change. Suggested-by: David Hildenbrand <david@redhat.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: David Rientjes <rientjes@google.com> Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@kernel.org> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Rik van Riel <riel@surriel.com> Link: http://lkml.kernel.org/r/20200317100342.2730705-1-ying.huang@intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm: remove CONFIG_TRANSPARENT_HUGE_PAGECACHEMatthew Wilcox (Oracle)
Commit e496cf3d7821 ("thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE") notes that it should be reverted when the PowerPC problem was fixed. The commit fixing the PowerPC problem (953c66c2b22a) did not revert the commit; instead setting CONFIG_TRANSPARENT_HUGE_PAGECACHE to the same as CONFIG_TRANSPARENT_HUGEPAGE. Checking with Kirill and Aneesh, this was an oversight, so remove the Kconfig symbol and undo the work of commit e496cf3d7821. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Link: http://lkml.kernel.org/r/20200318140253.6141-6-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07include/linux/pagemap.h: optimise find_subpage for !THPMatthew Wilcox (Oracle)
If THP is disabled, find_subpage() can become a no-op by using hpage_nr_pages() instead of compound_nr(). hpage_nr_pages() embeds a check for PageTail, so we can drop the check here. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Link: http://lkml.kernel.org/r/20200318140253.6141-5-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm, thp: track fallbacks due to failed memcg charges separatelyDavid Rientjes
The thp_fault_fallback and thp_file_fallback vmstats are incremented if either the hugepage allocation fails through the page allocator or the hugepage charge fails through mem cgroup. This patch leaves this field untouched but adds two new fields, thp_{fault,file}_fallback_charge, which is incremented only when the mem cgroup charge fails. This distinguishes between attempted hugepage allocations that fail due to fragmentation (or low memory conditions) and those that fail due to mem cgroup limits. That can be used to determine the impact of fragmentation on the system by excluding faults that failed due to memcg usage. Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Jeremy Cline <jcline@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2003061422070.7412@chino.kir.corp.google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm, shmem: add vmstat for hugepage fallbackDavid Rientjes
The existing thp_fault_fallback indicates when thp attempts to allocate a hugepage but fails, or if the hugepage cannot be charged to the mem cgroup hierarchy. Extend this to shmem as well. Adds a new thp_file_fallback to complement thp_file_alloc that gets incremented when a hugepage is attempted to be allocated but fails, or if it cannot be charged to the mem cgroup hierarchy. Additionally, remove the check for CONFIG_TRANSPARENT_HUGE_PAGECACHE from shmem_alloc_hugepage() since it is only called with this configuration option. Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Jeremy Cline <jcline@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2003061421240.7412@chino.kir.corp.google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm: make it clear that gfp reclaim modifiers are valid only for sleepable ↵Michal Hocko
allocations While it might be really clear to MM developers that gfp reclaim modifiers are applicable only to sleepable allocations (those with __GFP_DIRECT_RECLAIM) it seems that actual users of the API are not always sure. Make it explicit that they are not applicable for GFP_NOWAIT or GFP_ATOMIC allocations which are the most commonly used non-sleepable allocation masks. Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Neil Brown <neilb@suse.de> Link: http://lkml.kernel.org/r/20200403083543.11552-3-mhocko@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/vma: replace all remaining open encodings with is_vm_hugetlb_page()Anshuman Khandual
This replaces all remaining open encodings with is_vm_hugetlb_page(). Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Will Deacon <will@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Nick Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1582520593-30704-4-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/vma: make vma_is_accessible() available for general useAnshuman Khandual
Lets move vma_is_accessible() helper to include/linux/mm.h which makes it available for general use. While here, this replaces all remaining open encodings for VMA access check with vma_is_accessible(). Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Guo Ren <guoren@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Guo Ren <guoren@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paulburton@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Nick Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/1582520593-30704-3-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/vma: add missing VMA flag readable name for VM_SYNCAnshuman Khandual
Patch series "mm/vma: Use all available wrappers when possible", v2. Apart from adding a VMA flag readable name for trace purpose, this series does some open encoding replacements with availabe VMA specific wrappers. This skips VM_HUGETLB check in vma_migratable() as its already being done with another patch (https://patchwork.kernel.org/patch/11347831/) which is yet to be merged. This patch (of 4): This just adds the missing readable name for VM_SYNC. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nick Piggin <npiggin@gmail.com> Cc: Paul Burton <paulburton@kernel.org> Cc: Paul Mackerras <paulus@ozlabs.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: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1582520593-30704-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07Bluetooth: debugfs option to unset MITM flagArchie Pusaka
The BT qualification test SM/MAS/PKE/BV-01-C needs us to turn off the MITM flag when pairing, and at the same time also set the io capability to something other than no input no output. Currently the MITM flag is only unset when the io capability is set to no input no output, therefore the test cannot be executed. This patch introduces a debugfs option to force MITM flag to be turned off. Signed-off-by: Archie Pusaka <apusaka@chromium.org> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-04-07netfilter: nf_tables: reintroduce the NFT_SET_CONCAT flagPablo Neira Ayuso
Stefano originally proposed to introduce this flag, users hit EOPNOTSUPP in new binaries with old kernels when defining a set with ranges in a concatenation. Fixes: f3a2181e16f1 ("netfilter: nf_tables: Support for sets with multiple ranged fields") Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-04-07xen: Use evtchn_type_t as a type for event channelsYan Yankovskyi
Make event channel functions pass event channel port using evtchn_port_t type. It eliminates signed <-> unsigned conversion. Signed-off-by: Yan Yankovskyi <yyankovskyi@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20200323152343.GA28422@kbp1-lhp-F74019 Signed-off-by: Juergen Gross <jgross@suse.com>
2020-04-07thermal: devfreq_cooling: inline all stubs for CONFIG_DEVFREQ_THERMAL=nMartin Blumenstingl
When CONFIG_DEVFREQ_THERMAL is disabled all functions except of_devfreq_cooling_register_power() were already inlined. Also inline the last function to avoid compile errors when multiple drivers call of_devfreq_cooling_register_power() when CONFIG_DEVFREQ_THERMAL is not set. Compilation failed with the following message: multiple definition of `of_devfreq_cooling_register_power' (which then lists all usages of of_devfreq_cooling_register_power()) Thomas Zimmermann reported this problem [0] on a kernel config with CONFIG_DRM_LIMA={m,y}, CONFIG_DRM_PANFROST={m,y} and CONFIG_DEVFREQ_THERMAL=n after both, the lima and panfrost drivers gained devfreq cooling support. [0] https://www.spinics.net/lists/dri-devel/msg252825.html Fixes: a76caf55e5b356 ("thermal: Add devfreq cooling") Cc: stable@vger.kernel.org Reported-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200403205133.1101808-1-martin.blumenstingl@googlemail.com
2020-04-06Merge branch 'next' into for-linusDmitry Torokhov
Prepare input updates for 5.7 merge window.
2020-04-06leds: make functions easier to understandPavel Machek
Group LED functions according to functionality, and add some explaining comments. Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-04-06leds: old enums are not really applicable to new codePavel Machek
Warn about old defines that probably should not be used. Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-04-06NFS: Clean up process of marking inode stale.Trond Myklebust
Instead of the various open coded calls to set the NFS_INO_STALE bit and call nfs_zap_caches(), consolidate them into a single function nfs_set_inode_stale(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-06Merge tag 'acpi-5.7-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI updates from Rafael Wysocki: "Additional ACPI updates. These update the ACPICA code in the kernel to the 20200326 upstream revision, fix an ACPI-related CPU hotplug deadlock on x86, update Intel Tiger Lake device IDs in some places, add a new ACPI backlight blacklist entry, update the "acpi_backlight" kernel command line switch documentation and clean up a CPPC library routine. Specifics: - Update the ACPICA code in the kernel to upstream revision 20200326 including: * Fix for a typo in a comment field (Bob Moore) * acpiExec namespace init file fixes (Bob Moore) * Addition of NHLT to the known tables list (Cezary Rojewski) * Conversion of PlatformCommChannel ASL keyword to PCC (Erik Kaneda) * acpiexec cleanup (Erik Kaneda) * WSMT-related typo fix (Erik Kaneda) * sprintf() utility function fix (John Levon) * IVRS IVHD type 11h parsing implementation (Michał Żygowski) * IVRS IVHD type 10h reserved field name fix (Michał Żygowski) - Fix ACPI-related CPU hotplug deadlock on x86 (Qian Cai) - Fix Intel Tiger Lake ACPI device IDs in several places (Gayatri Kammela) - Add ACPI backlight blacklist entry for Acer Aspire 5783z (Hans de Goede) - Fix documentation of the "acpi_backlight" kernel command line switch (Randy Dunlap) - Clean up the acpi_get_psd_map() CPPC library routine (Liguang Zhang)" * tag 'acpi-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: x86: ACPI: fix CPU hotplug deadlock thermal: int340x_thermal: fix: Update Tiger Lake ACPI device IDs platform/x86: intel-hid: fix: Update Tiger Lake ACPI device ID ACPI: Update Tiger Lake ACPI device IDs ACPI: video: Use native backlight on Acer Aspire 5783z ACPI: video: Docs update for "acpi_backlight" kernel parameter options ACPICA: Update version 20200326 ACPICA: Fixes for acpiExec namespace init file ACPICA: Add NHLT table signature ACPICA: WSMT: Fix typo, no functional change ACPICA: utilities: fix sprintf() ACPICA: acpiexec: remove redeclaration of acpi_gbl_db_opt_no_region_support ACPICA: Change PlatformCommChannel ASL keyword to PCC ACPICA: Fix IVRS IVHD type 10h reserved field name ACPICA: Implement IVRS IVHD type 11h parsing ACPICA: Fix a typo in a comment field ACPI: CPPC: clean up acpi_get_psd_map()
2020-04-06skbuff.h: Improve the checksum related commentsDexuan Cui
Fixed the punctuation and some typos. Improved some sentences with minor changes. No change of semantics or code. Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-06Merge tag 'pm-5.7-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "Additional power management updates. These fix a corner-case suspend-to-idle wakeup issue on systems where the ACPI SCI is shared with another wakeup source, add a kernel command line option to set pm_debug_messages via the kernel command line, add a document desctibing system-wide suspend and resume code flows, modify cpufreq Kconfig to choose schedutil as the preferred governor by default in a couple of cases and do some assorted cleanups. Specifics: - Fix corner-case suspend-to-idle wakeup issue on systems where the ACPI SCI is shared with another wakeup source (Hans de Goede). - Add document describing system-wide suspend and resume code flows to the admin guide (Rafael Wysocki). - Add kernel command line option to set pm_debug_messages (Chen Yu). - Choose schedutil as the preferred scaling governor by default on ARM big.LITTLE systems and on x86 systems using the intel_pstate driver in the passive mode (Linus Walleij, Rafael Wysocki). - Drop racy and redundant checks from the PM core's device_prepare() routine (Rafael Wysocki). - Make resume from hibernation take the hibernation_restore() return value into account (Dexuan Cui)" * tag 'pm-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: platform/x86: intel_int0002_vgpio: Use acpi_register_wakeup_handler() ACPI: PM: Add acpi_[un]register_wakeup_handler() Documentation: PM: sleep: Document system-wide suspend code flows cpufreq: Select schedutil when using big.LITTLE PM: sleep: Add pm_debug_messages kernel command line option PM: sleep: core: Drop racy and redundant checks from device_prepare() PM: hibernate: Propagate the return value of hibernation_restore() cpufreq: intel_pstate: Select schedutil as the default governor
2020-04-06Merge tag 'fsnotify_for_v5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: "This implements the fanotify FAN_DIR_MODIFY event. This event reports the name in a directory under which a change happened and together with the directory filehandle and fstatat() allows reliable and efficient implementation of directory synchronization" * tag 'fsnotify_for_v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fanotify: Fix the checks in fanotify_fsid_equal fanotify: report name info for FAN_DIR_MODIFY event fanotify: record name info for FAN_DIR_MODIFY event fanotify: Drop fanotify_event_has_fid() fanotify: prepare to report both parent and child fid's fanotify: send FAN_DIR_MODIFY event flavor with dir inode and name fanotify: divorce fanotify_path_event and fanotify_fid_event fanotify: Store fanotify handles differently fanotify: Simplify create_fd() fanotify: fix merging marks masks with FAN_ONDIR fanotify: merge duplicate events on parent and child fsnotify: replace inode pointer with an object id fsnotify: simplify arguments passing to fsnotify_parent() fsnotify: use helpers to access data by data_type fsnotify: funnel all dirent events through fsnotify_name() fsnotify: factor helpers fsnotify_dentry() and fsnotify_file() fsnotify: tidy up FS_ and FAN_ constants
2020-04-06Merge tag '9p-for-5.7' of git://github.com/martinetd/linuxLinus Torvalds
Pull 9p updates from Dominique Martinet: "Not much new, but a few patches for this cycle: - Fix read with O_NONBLOCK to allow incomplete read and return immediately - Rest is just cleanup (indent, unused field in struct, extra semicolon)" * tag '9p-for-5.7' of git://github.com/martinetd/linux: net/9p: remove unused p9_req_t aux field 9p: read only once on O_NONBLOCK 9pnet: allow making incomplete read requests 9p: Remove unneeded semicolon 9p: Fix Kconfig indentation
2020-04-06Merge branch 'acpica'Rafael J. Wysocki
* acpica: ACPICA: Update version 20200326 ACPICA: Fixes for acpiExec namespace init file ACPICA: Add NHLT table signature ACPICA: WSMT: Fix typo, no functional change ACPICA: utilities: fix sprintf() ACPICA: acpiexec: remove redeclaration of acpi_gbl_db_opt_no_region_support ACPICA: Change PlatformCommChannel ASL keyword to PCC ACPICA: Fix IVRS IVHD type 10h reserved field name ACPICA: Implement IVRS IVHD type 11h parsing ACPICA: Fix a typo in a comment field
2020-04-05netfilter: xt_IDLETIMER: target v1 - match Android layoutMaciej Żenczykowski
Android has long had an extension to IDLETIMER to send netlink messages to userspace, see: https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/include/uapi/linux/netfilter/xt_IDLETIMER.h#42 Note: this is idletimer target rev 1, there is no rev 0 in the Android common kernel sources, see registration at: https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/net/netfilter/xt_IDLETIMER.c#483 When we compare that to upstream's new idletimer target rev 1: https://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next.git/tree/include/uapi/linux/netfilter/xt_IDLETIMER.h#n46 We immediately notice that these two rev 1 structs are the same size and layout, and that while timer_type and send_nl_msg are differently named and serve a different purpose, they're at the same offset. This makes them impossible to tell apart - and thus one cannot know in a mixed Android/vanilla environment whether one means timer_type or send_nl_msg. Since this is iptables/netfilter uapi it introduces a problem between iptables (vanilla vs Android) userspace and kernel (vanilla vs Android) if the two don't match each other. Additionally when at some point in the future Android picks up 5.7+ it's not at all clear how to resolve the resulting merge conflict. Furthermore, since upgrading the kernel on old Android phones is pretty much impossible there does not seem to be an easy way out of this predicament. The only thing I've been able to come up with is some super disgusting kernel version >= 5.7 check in the iptables binary to flip between different struct layouts. By adding a dummy field to the vanilla Linux kernel header file we can force the two structs to be compatible with each other. Long term I think I would like to deprecate send_nl_msg out of Android entirely, but I haven't quite been able to figure out exactly how we depend on it. It seems to be very similar to sysfs notifications but with some extra info. Currently it's actually always enabled whenever Android uses the IDLETIMER target, so we could also probably entirely remove it from the uapi in favour of just always enabling it, but again we can't upgrade old kernels already in the field. (Also note that this doesn't change the structure's size, as it is simply fitting into the pre-existing padding, and that since 5.7 hasn't been released yet, there's still time to make this uapi visible change) Cc: Manoj Basapathi <manojbm@codeaurora.org> Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-04-05netfilter: nf_tables: do not update stateful expressions if lookup is invertedPablo Neira Ayuso
Initialize set lookup matching element to NULL. Otherwise, the NFT_LOOKUP_F_INV flag reverses the matching logic and it leads to deference an uninitialized pointer to the matching element. Make sure element data area and stateful expression are accessed if there is a matching set element. This patch undoes 24791b9aa1ab ("netfilter: nft_set_bitmap: initialize set element extension in lookups") which is not required anymore. Fixes: 339706bc21c1 ("netfilter: nft_lookup: update element stateful expression") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-04-05Merge tag 'for-v5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply Pull power supply and reset changes from Sebastian Reichel: "Core: - Nothing Drivers: - at91-reset: cleanups, proper handling for sam9x60 - sc27xx, charger-manager: allow building as module - sc27xx: add support to read current charge capacity - axp288: more quirks for weird hardware - misc fixes" * tag 'for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply: (26 commits) power: reset: sc27xx: Allow the SC27XX poweroff driver building into a module power: reset: sc27xx: Change to use cpu_down() power: reset: sc27xx: Power off the external subsystems' connection power: twl4030: Use scnprintf() for avoiding potential buffer overflow power: supply: bq27xxx_battery: Silence deferred-probe error power: reset: at91-reset: handle nrst async for sam9x60 power: reset: at91-reset: get rid of at91_reset_data power: reset: at91-reset: keep only one reset function power: reset: at91-reset: make at91sam9g45_restart() generic power: reset: at91-reset: introduce ramc_lpr to struct at91_reset power: reset: at91-reset: use r4 as tmp argument power: reset: at91-reset: introduce args member in at91_reset_data power: reset: at91-reset: introduce struct at91_reset_data power: reset: at91-reset: devm_kzalloc() for at91_reset data structure power: reset: at91-reset: pass rstc base address to at91_reset_status() power: reset: at91-reset: convert reset in pointer to struct at91_reset power: reset: at91-reset: add notifier block to struct at91_reset power: reset: at91-reset: add sclk to struct at91_reset power: reset: at91-reset: add ramc_base[] to struct at91_reset power: reset: at91-reset: introduce struct at91_reset ...
2020-04-05Merge tag 'perf-urgent-2020-04-05' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more perf updates from Thomas Gleixner: "Perf updates all over the place: core: - Support for cgroup tracking in samples to allow cgroup based analysis tools: - Support for cgroup analysis - Commandline option and hotkey for perf top to change the sort order - A set of fixes all over the place - Various build system related improvements - Updates of the X86 pmu event JSON data - Documentation updates" * tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits) perf python: Fix clang detection to strip out options passed in $CC perf tools: Support Python 3.8+ in Makefile perf script: Fix invalid read of directory entry after closedir() perf script report: Fix SEGFAULT when using DWARF mode perf script: add -S/--symbols documentation perf pmu-events x86: Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric perf events parser: Add missing Intel CPU events to parser perf script: Allow --symbol to accept hexadecimal addresses perf report/top TUI: Fix title line formatting perf top: Support hotkey to change sort order perf top: Support --group-sort-idx to change the sort order perf symbols: Fix arm64 gap between kernel start and module end perf build-test: Honour JOBS to override detection of number of cores perf script: Add --show-cgroup-events option perf top: Add --all-cgroups option perf record: Add --all-cgroups option perf record: Support synthesizing cgroup events perf report: Add 'cgroup' sort key perf cgroup: Maintain cgroup hierarchy perf tools: Basic support for CGROUP event ...
2020-04-05Merge tag 'timers-urgent-2020-04-05' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Two timer subsystem fixes: - Prevent a use after free in the new lockdep state tracking for hrtimers - Add missing parenthesis in the VF pit timer driver" * tag 'timers-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/timer-vf-pit: Add missing parenthesis hrtimer: Don't dereference the hrtimer pointer after the callback
2020-04-05sysfs: remove redundant __compat_only_sysfs_link_entry_to_kobj fnLinus Torvalds
Commit 9255782f7061 ("sysfs: Wrap __compat_only_sysfs_link_entry_to_kobj function to change the symlink name") made this function a wrapper around a new non-underscored function, which is a bit odd. The normal naming convention is the other way around: the underscored function is the wrappee, and the non-underscored function is the wrapper. There's only one single user (well, two call-sites in that user) of the more limited double underscore version of this function, so just remove the oddly named wrapper entirely and just add the extra NULL argument to the user. I considered just doing that in the merge, but that tends to make history really hard to read. Link: https://lore.kernel.org/lkml/CAHk-=wgkkmNV5tMzQDmPAQuNJBuMcry--Jb+h8H1o4RA3kF7QQ@mail.gmail.com/ Cc: Sourabh Jain <sourabhjain@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-05Merge tag 'powerpc-5.7-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly late as I had to rebase mid-week to insert a bug fix: - A large series from Nick for 64-bit to further rework our exception vectors, and rewrite portions of the syscall entry/exit and interrupt return in C. The result is much easier to follow code that is also faster in general. - Cleanup of our ptrace code to split various parts out that had become badly intertwined with #ifdefs over the years. - Changes to our NUMA setup under the PowerVM hypervisor which should hopefully avoid non-sensical topologies which can lead to warnings from the workqueue code and other problems. - MAINTAINERS updates to remove some of our old orphan entries and update the status of others. - Quite a few other small changes and fixes all over the map. Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing" * tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits) powerpc: Make setjmp/longjmp signature standard powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type powerpc: Suppress .eh_frame generation powerpc: Drop -fno-dwarf2-cfi-asm powerpc/32: drop unused ISA_DMA_THRESHOLD powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces selftests/powerpc: Fix try-run when source tree is not writable powerpc/vmlinux.lds: Explicitly retain .gnu.hash powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c powerpc/ptrace: create ppc_gethwdinfo() powerpc/ptrace: create ptrace_get_debugreg() powerpc/ptrace: split out ADV_DEBUG_REGS related functions. powerpc/ptrace: move register viewing functions out of ptrace.c powerpc/ptrace: split out TRANSACTIONAL_MEM related functions. powerpc/ptrace: split out SPE related functions. powerpc/ptrace: split out ALTIVEC related functions. powerpc/ptrace: split out VSX related functions. powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64 powerpc/ptrace: remove unused header includes ...
2020-04-05Merge tag 'random_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull /dev/random updates from Ted Ts'o: - Improve getrandom and /dev/random's support for those arm64 architecture variants that have RNG instructions. - Use batched output from CRNG instead of CPU's RNG instructions for better performance. - Miscellaneous bug fixes. * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: avoid warnings for !CONFIG_NUMA builds random: fix data races at timer_rand_state random: always use batched entropy for get_random_u{32,64} random: Make RANDOM_TRUST_CPU depend on ARCH_RANDOM arm64: add credited/trusted RNG support random: add arch_get_random_*long_early() random: split primary/secondary crng init paths
2020-04-05Merge tag 'clk-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk updates from Stephen Boyd: "There's not much to see in the core framework this time around. Instead the majority of the diff is the normal collection of driver additions for new SoCs and non-critical clk data fixes and updates. The framework must be middle aged. The two biggest directories in the diffstat show that the Qualcomm and Unisoc support added a handful of big drivers for new SoCs but that's not really the whole story because those new drivers tend to add large numbers of lines of clk data. There's a handful of AT91 clk drivers added this time around too and a bunch of improvements to drivers like the i.MX driver. All around lots of updates and fixes in various clk drivers which is good to see. The core framework has only one real major change which has been baking in next for the past couple months. It fixes the framework so that it stops caching a clk's phase when the phase clk_op returns an error. Before this change we would consider some negative errno as a phase and that just doesn't make sense. Core: - Don't show clk phase when it is invalid New Drivers: - Add support for Unisoc SC9863A clks - Qualcomm SM8250 RPMh and MSM8976 RPM clks - Qualcomm SM8250 Global Clock Controller (GCC) support - Qualcomm SC7180 Modem Clock Controller (MSS CC) support - EHRPWM's TimeBase clock(TBCLK) for TI AM654 SoCs - Support PMC clks on at91sam9n12, at91rm9200, sama5d3, and at91sam9g45 SoCs Updates: - GPU GX GDSC support on Qualcomm sc7180 - Fixes and improvements for the Marvell MMP2/MMP3 SoC clk drivers - A series from Anson to convert i.MX8 clock bindings to json-schema - Update i.MX pll14xx driver to include new frequency entries for pll1443x table, and return error for invalid PLL type - Add missing of_node_put() call for a number of i.MX clock drivers - Drop flag CLK_IS_CRITICAL from 'A53_CORE' mux clock, as we already have the flag on its child cpu clock - Fix a53 cpu clock for i.MX8 drivers to get it source from ARM PLL via CORE_SEL slice, and source from A53 CCM clk root when we need to change ARM PLL frequency. Thus, we can support core running above 1GHz safely - Update i.MX pfdv2 driver to check zero rate and use determine_rate for getting the best rate - Add CLKO2 for imx8mm, SNVS clock for imx8mn, and PXP clock for imx7d - Remove PMC clks from Tegra clk driver - Improved clock/reset handling for the Renesas R-Car USB2 Clock Selector - Conversion to json-schema of the Renesas CPG/MSSR DT bindings - Add Crypto clocks on Renesas R-Car M3-W/W+, M3-N, E3, and D3 - Add RPC (QSPI/HyperFLASH) clocks on Renesas R-Car H3, M3-W/W+, and M3-N - Update Amlogic audio clock gate hierarchy for meson8 and gxbb - Update Amlogic g12a spicc clock sources - Support for Ingenic X1000 TCU clks" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (146 commits) clk: sprd: fix to get a correct ibias of pll dt-bindings: imx8mm-clock: Fix the file path dt-bindings: imx8mq-clock: Fix the file path clk: qcom: rpmh: Drop unnecessary semicolons clk: qcom: rpmh: Simplify clk_rpmh_bcm_send_cmd() clk: tegra: Use NULL for pointer initialization clk: sprd: add clocks support for SC9863A clk: sprd: support to get regmap from parent node clk: sprd: Add macros for referencing parents without strings clk: sprd: Add dt-bindings include file for SC9863A dt-bindings: clk: sprd: add bindings for sc9863a clock controller dt-bindings: clk: sprd: rename the common file name sprd.txt to SoC specific clk: sprd: add gate for pll clocks MAINTAINERS: dt: update reference for arm-integrator.txt clk: mmp2: Fix bit masks for LCDC I/O and pixel clocks clk: mmp2: Add clock for fifth SD HCI on MMP3 dt-bindings: marvell,mmp2: Add clock id for the fifth SD HCI on MMP3 clk: mmp2: Add clocks for the thermal sensors dt-bindings: marvell,mmp2: Add clock ids for the thermal sensors clk: mmp2: add the GPU clocks ...
2020-04-05Merge tag 'trace-v5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New tracing features: - The ring buffer is no longer disabled when reading the trace file. The trace_pipe file was made to be used for live tracing and reading as it acted like the normal producer/consumer. As the trace file would not consume the data, the easy way of handling it was to just disable writes to the ring buffer. This came to a surprise to the BPF folks who complained about lost events due to reading. This is no longer an issue. If someone wants to keep the old disabling there's a new option "pause-on-trace" that can be set. - New set_ftrace_notrace_pid file. PIDs in this file will not be traced by the function tracer. Similar to set_ftrace_pid, which makes the function tracer only trace those tasks with PIDs in the file, the set_ftrace_notrace_pid does the reverse. - New set_event_notrace_pid file. PIDs in this file will cause events not to be traced if triggered by a task with a matching PID. Similar to the set_event_pid file but will not be traced. Note, sched_waking and sched_switch events may still be traced if one of the tasks referenced by those events contains a PID that is allowed to be traced. Tracing related features: - New bootconfig option, that is attached to the initrd file. If bootconfig is on the command line, then the initrd file is searched looking for a bootconfig appended at the end. - New GPU tracepoint infrastructure to help the gfx drivers to get off debugfs (acked by Greg Kroah-Hartman) And other minor updates and fixes" * tag 'trace-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (27 commits) tracing: Do not allocate buffer in trace_find_next_entry() in atomic tracing: Add documentation on set_ftrace_notrace_pid and set_event_notrace_pid selftests/ftrace: Add test to test new set_event_notrace_pid file selftests/ftrace: Add test to test new set_ftrace_notrace_pid file tracing: Create set_event_notrace_pid to not trace tasks ftrace: Create set_ftrace_notrace_pid to not trace tasks ftrace: Make function trace pid filtering a bit more exact ftrace/kprobe: Show the maxactive number on kprobe_events tracing: Have the document reflect that the trace file keeps tracing enabled ring-buffer/tracing: Have iterator acknowledge dropped events tracing: Do not disable tracing when reading the trace file ring-buffer: Do not disable recording when there is an iterator ring-buffer: Make resize disable per cpu buffer instead of total buffer ring-buffer: Optimize rb_iter_head_event() ring-buffer: Do not die if rb_iter_peek() fails more than thrice ring-buffer: Have rb_iter_head_event() handle concurrent writer ring-buffer: Add page_stamp to iterator for synchronization ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance() ring-buffer: Have ring_buffer_empty() not depend on tracing stopped tracing: Save off entry when peeking at next entry ...
2020-04-05Bluetooth: Add HCI device identifier for VIRTIO devicesMarcel Holtmann
This patch assigns the next free HCI device identifier to Bluetooth devices based on VIRTIO devices. Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-04-05Bluetooth: Add support for reading security informationMarcel Holtmann
To allow userspace to make correcty security policy decision, the kernel needs to export a few details of the supported security features and encryption key size information. This command exports this information and also allows future extensions if needed. Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Alain Michaud <alainm@chromium.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-04-05Bluetooth: Add support for Read Local Simple Pairing OptionsMarcel Holtmann
With the Read Local Simple Pairing Options command it is possible to retrieve the support for max encryption key size supported by the controller and also if the controller correctly verifies the ECDH public key during pairing. Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Alain Michaud <alainm@chromium.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-04-05Bluetooth: Add framework for Microsoft vendor extensionMiao-chen Chou
Micrsoft defined a set for HCI vendor extensions. Check the following link for details: https://docs.microsoft.com/en-us/windows-hardware/drivers/bluetooth/microsoft-defined-bluetooth-hci-commands-and-events This provides the basic framework to enable the extension and read its supported features. Drivers still have to declare support for this extension before it can be utilized by the host stack. Signed-off-by: Miao-chen Chou <mcchou@chromium.org> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-04-05Bluetooth: add support to notify using SCO air modeSathish Narsimman
notifying using HCI_NOTIFY_CONN_ADD for SCO connection is generic in case of mSBC audio. To differntiate SCO air mode introducing HCI_NOTIFY_ENABLE_SCO_CVSD and HCI_NOTIFY_ENABLE_SCO_TRANSP. Signed-off-by: Sathish Narsimman <sathish.narasimman@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2020-04-04Merge tag 'keys-fixes-20200329' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull keyrings fixes from David Howells: "Here's a couple of patches that fix a circular dependency between holding key->sem and mm->mmap_sem when reading data from a key. One potential issue is that a filesystem looking to use a key inside, say, ->readpages() could deadlock if the key being read is the key that's required and the buffer the key is being read into is on a page that needs to be fetched. The case actually detected is a bit more involved - with a filesystem calling request_key() and locking the target keyring for write - which could be being read" * tag 'keys-fixes-20200329' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: KEYS: Avoid false positive ENOMEM error on key read KEYS: Don't write out to userspace while holding key semaphore
2020-04-04Merge tag 'drm-next-2020-04-03-1' of git://anongit.freedesktop.org/drm/drmLinus Torvalds
Pull drm hugepage support from Dave Airlie: "This adds support for hugepages to TTM and has been tested with the vmwgfx drivers, though I expect other drivers to start using it" * tag 'drm-next-2020-04-03-1' of git://anongit.freedesktop.org/drm/drm: drm/vmwgfx: Hook up the helpers to align buffer objects drm/vmwgfx: Introduce a huge page aligning TTM range manager drm: Add a drm_get_unmapped_area() helper drm/vmwgfx: Support huge page faults drm/ttm, drm/vmwgfx: Support huge TTM pagefaults mm: Add vmf_insert_pfn_xxx_prot() for huge page-table entries mm: Split huge pages on write-notify or COW mm: Introduce vma_is_special_huge fs: Constify vma argument to vma_is_dax
2020-04-04Merge tag 'nfsd-5.7' of git://git.linux-nfs.org/projects/cel/cel-2.6Linus Torvalds
Pull nfsd updates from Chuck Lever: - Fix EXCHANGE_ID response when NFSD runs in a container - A battery of new static trace points - Socket transports now use bio_vec to send Replies - NFS/RDMA now supports filesystems with no .splice_read method - Favor memcpy() over DMA mapping for small RPC/RDMA Replies - Add pre-requisites for supporting multiple Write chunks - Numerous minor fixes and clean-ups [ Chuck is filling in for Bruce this time while he and his family settle into a new house ] * tag 'nfsd-5.7' of git://git.linux-nfs.org/projects/cel/cel-2.6: (39 commits) svcrdma: Fix leak of transport addresses SUNRPC: Fix a potential buffer overflow in 'svc_print_xprts()' SUNRPC/cache: don't allow invalid entries to be flushed nfsd: fsnotify on rmdir under nfsd/clients/ nfsd4: kill warnings on testing stateids with mismatched clientids nfsd: remove read permission bit for ctl sysctl NFSD: Fix NFS server build errors sunrpc: Add tracing for cache events SUNRPC/cache: Allow garbage collection of invalid cache entries nfsd: export upcalls must not return ESTALE when mountd is down nfsd: Add tracepoints for update of the expkey and export cache entries nfsd: Add tracepoints for exp_find_key() and exp_get_by_name() nfsd: Add tracing to nfsd_set_fh_dentry() nfsd: Don't add locks to closed or closing open stateids SUNRPC: Teach server to use xprt_sock_sendmsg for socket sends SUNRPC: Refactor xs_sendpages() svcrdma: Avoid DMA mapping small RPC Replies svcrdma: Fix double sync of transport header buffer svcrdma: Refactor chunk list encoders SUNRPC: Add encoders for list item discriminators ...
2020-04-04ACPI: PM: Add acpi_[un]register_wakeup_handler()Hans de Goede
Since commit fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system") the SCI triggering without there being a wakeup cause recognized by the ACPI sleep code will no longer wakeup the system. This works as intended, but this is a problem for devices where the SCI is shared with another device which is also a wakeup source. In the past these, from the pov of the ACPI sleep code, spurious SCIs would still cause a wakeup so the wakeup from the device sharing the interrupt would actually wakeup the system. This now no longer works. This is a problem on e.g. Bay Trail-T and Cherry Trail devices where some peripherals (typically the XHCI controller) can signal a Power Management Event (PME) to the Power Management Controller (PMC) to wakeup the system, this uses the same interrupt as the SCI. These wakeups are handled through a special INT0002 ACPI device which checks for events in the GPE0a_STS for this and takes care of acking the PME so that the shared interrupt stops triggering. The change to the ACPI sleep code to ignore the spurious SCI, causes the system to no longer wakeup on these PME events. To make things worse this means that the INT0002 device driver interrupt handler will no longer run, causing the PME to not get cleared and resulting in the system hanging. Trying to wakeup the system after such a PME through e.g. the power button no longer works. Add an acpi_register_wakeup_handler() function which registers a handler to be called from acpi_s2idle_wake() and when the handler returns true, return true from acpi_s2idle_wake(). The INT0002 driver will use this mechanism to check the GPE0a_STS register from acpi_s2idle_wake() and to tell the system to wakeup if a PME is signaled in the register. Fixes: fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system") Cc: 5.4+ <stable@vger.kernel.org> # 5.4+ Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-04Merge tag 'rtc-5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "More cleanup this cycle, with the final goal of removing the rtc_time_to_tm and rtc_tm_to_time wrappers. All the drivers that have been modified for this now are ready for the end of times (whether it happens in 2033, 2038, 2106, 2127 or even 4052). There is also a single new driver and the usual fixes and features. Summary: Subsystem: - The rtc_time_to_tm and rtc_tm_to_time wrappers have finally been removed and only the 64bit version remain. - hctosys now works with drivers compiled as modules New driver: - MediaTek MT2712 SoC based RTC Drivers: - set range for 88pm860x, au1xxx, cpcap, da9052, davinci, ds1305, ds1374, mcp5121, pl030, pl031, pm8xxx, puv3, sa1100, sirfsoc, starfire, sun6i - ds1307: DS1388 oscillator failure detection and watchdog support - jz4740: JZ4760 support - pcf85063: clock out pin support - sun6i: external 32k oscillator is now optional, the range is now handled by the core, providing a solution for 2034" * tag 'rtc-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (87 commits) rtc: ds1307: check for failed memory allocation on wdt rtc: class: remove redundant assignment to variable err rtc: remove rtc_time_to_tm and rtc_tm_to_time rtc: sun6i: let the core handle rtc range rtc: sun6i: switch to rtc_time64_to_tm/rtc_tm_to_time64 rtc: ds1307: add support for watchdog timer on ds1388 rtc: da9052: switch to rtc_time64_to_tm/rtc_tm_to_time64 rtc: da9052: set range rtc: da9052: convert to devm_rtc_allocate_device rtc: imx-sc: Align imx sc msg structs to 4 rtc: fsl-ftm-alarm: report alarm to core rtc: pcf85063: Add pcf85063 clkout control to common clock framework rtc: make definitions in include/uapi/linux/rtc.h actually useful for user space rtc: class: avoid unnecessary lookup in hctosys dt-bindings: rtc: Convert and update jz4740-rtc doc to YAML rtc: jz4740: Rename vendor-specific DT properties rtc: jz4740: Add support for JZ4760 SoC rtc: class: support hctosys from modular RTC drivers rtc: pm8xxx: clear alarm register when alarm is not enabled rtc: omap: drop unused dt-bindings header ...
2020-04-04Merge tag 'gpio-v5.7-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO development for the v5.7 kernel cycle. Core and userspace API: - The userspace API KFIFOs have been imoproved with locks that do not block interrupts. This makes us better at getting events to userspace without blocking or disturbing new events arriving in the same time. This was reviewed by the KFIFO maintainer Stefani. This is a generic improvement which paves the road for similar improvements in other subsystems. - We provide a new ioctl() for monitoring changes in the line information, such as when multiple clients are taking lines and giving them back, possibly reconfiguring them in the process: we can now monitor that and not get stuck with stale static information. - An example tool 'gpio-watch' is provided to showcase this functionality. - Timestamps for events are switched to ktime_get_ns() which is monotonic. We previously had a 'realtime' stamp which could move forward and *backward* in time, which probably would just cause silent bugs and weird behaviour. In the long run we see two relevant timestamps: ktime_get_ns() or the timestamp sometimes provided by the GPIO hardware itself, if that exists. - Device Tree overlay support for GPIO hogs. On systems that load overlays, these overlays can now contain hogs, and will then be respected. - Handle pin control interaction with nonexisting pin ranges in the GPIO library core instead of in the individual drivers. New drivers: - New driver for the Mellanox BlueField 2 GPIO controller. Driver improvements: - Introduce the BGPIOF_NO_SET_ON_INPUT flag to the generic MMIO GPIO library and use this flag in the MT7621 driver. - Texas Instruments OMAP CPU power management improvements, such as blocking of idle on pending GPIO interrupts" * tag 'gpio-v5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (59 commits) Revert "gpio: eic-sprd: Use devm_platform_ioremap_resource()" pinctrl: Unconditionally assign .request()/.free() gpio: Unconditionally assign .request()/.free() gpio: export of_pinctrl_get to modules pinctrl: Define of_pinctrl_get() dummy for !PINCTRL gpio: Rename variable in core APIs gpio: Avoid using pin ranges with !PINCTRL gpiolib: Remove unused gpio_chip parameter from gpio_set_bias() gpiolib: Pass gpio_desc to gpio_set_config() gpiolib: Introduce gpiod_set_config() tools: gpio: Fix out-of-tree build regression gpio: gpiolib: fix a doc warning gpio: tegra186: Add Tegra194 pin ranges for GG.0 and GG.1 gpio: tegra186: Add support for pin ranges gpio: Support GPIO controllers without pin-ranges ARM: integrator: impd1: Use GPIO_LOOKUP() helper macro gpio: brcmstb: support gpio-line-names property tools: gpio: Fix typo in gpio-utils tools: gpio-hammer: Apply scripts/Lindent and retain good changes gpiolib: gpio_name_to_desc: factor out !name check ...
2020-04-04Merge tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping updates from Christoph Hellwig: - fix an integer overflow in the coherent pool (Kevin Grandemange) - provide support for in-place uncached remapping and use that for openrisc - fix the arm coherent allocator to take the bus limit into account * tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping: ARM/dma-mapping: merge __dma_supported into arm_dma_supported ARM/dma-mapping: take the bus limit into account in __dma_alloc ARM/dma-mapping: remove get_coherent_dma_mask openrisc: use the generic in-place uncached DMA allocator dma-direct: provide a arch_dma_clear_uncached hook dma-direct: make uncached_kernel_address more general dma-direct: consolidate the error handling in dma_direct_alloc_pages dma-direct: remove the cached_kernel_address hook dma-coherent: fix integer overflow in the reserved-memory dma allocation
2020-04-04Merge tag 'vfio-v5.7-rc1' of git://github.com/awilliam/linux-vfioLinus Torvalds
Pull VFIO updates from Alex Williamson: - vfio-pci SR-IOV support (Alex Williamson) - vfio DMA read/write interface (Yan Zhao) - Fix vfio-platform erroneous IRQ error log (Eric Auger) - Fix shared ATSD support for NVLink on POWER (Sam Bobroff) - Fix init error without CONFIG_IOMMU_DMA (Andre Przywara) * tag 'vfio-v5.7-rc1' of git://github.com/awilliam/linux-vfio: vfio: Ignore -ENODEV when getting MSI cookie vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] vfio/pci: Cleanup .probe() exit paths vfio/pci: Remove dev_fmt definition vfio/pci: Add sriov_configure support vfio: Introduce VFIO_DEVICE_FEATURE ioctl and first user vfio/pci: Introduce VF token vfio/pci: Implement match ops vfio: Include optional device match in vfio_device_ops callbacks vfio: avoid inefficient operations on VFIO group in vfio_pin/unpin_pages vfio: introduce vfio_dma_rw to read/write a range of IOVAs vfio: allow external user to get vfio group from device vfio: platform: Switch to platform_get_irq_optional()
2020-04-04Merge tag 's390-5.7-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Update maintainers. Niklas Schnelle takes over zpci and Vineeth Vijayan common io code. - Extend cpuinfo to include topology information. - Add new extended counters for IBM z15 and sampling buffer allocation rework in perf code. - Add control over zeroing out memory during system restart. - CCA protected key block version 2 support and other fixes/improvements in crypto code. - Convert to new fallthrough; annotations. - Replace zero-length arrays with flexible-arrays. - QDIO debugfs and other small improvements. - Drop 2-level paging support optimization for compat tasks. Varios mm cleanups. - Remove broken and unused hibernate / power management support. - Remove fake numa support which does not bring any benefits. - Exclude offline CPUs from CPU topology masks to be more consistent with other architectures. - Prevent last branching instruction address leaking to userspace. - Other small various fixes and improvements all over the code. * tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits) s390/mm: cleanup init_new_context() callback s390/mm: cleanup virtual memory constants usage s390/mm: remove page table downgrade support s390/qdio: set qdio_irq->cdev at allocation time s390/qdio: remove unused function declarations s390/ccwgroup: remove pm support s390/ap: remove power management code from ap bus and drivers s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc s390/mm: cleanup arch_get_unmapped_area() and friends s390/ism: remove pm support s390/cio: use fallthrough; s390/vfio: use fallthrough; s390/zcrypt: use fallthrough; s390: use fallthrough; s390/cpum_sf: Fix wrong page count in error message s390/diag: fix display of diagnose call statistics s390/ap: Remove ap device suspend and resume callbacks s390/pci: Improve handling of unset UID s390/pci: Fix zpci_alloc_domain() over allocation s390/qdio: pass ISC as parameter to chsc_sadc() ...
2020-04-04x86: ACPI: fix CPU hotplug deadlockQian Cai
Similar to commit 0266d81e9bf5 ("acpi/processor: Prevent cpu hotplug deadlock") except this is for acpi_processor_ffh_cstate_probe(): "The problem is that the work is scheduled on the current CPU from the hotplug thread associated with that CPU. It's not required to invoke these functions via the workqueue because the hotplug thread runs on the target CPU already. Check whether current is a per cpu thread pinned on the target CPU and invoke the function directly to avoid the workqueue." WARNING: possible circular locking dependency detected ------------------------------------------------------ cpuhp/1/15 is trying to acquire lock: ffffc90003447a28 ((work_completion)(&wfc.work)){+.+.}-{0:0}, at: __flush_work+0x4c6/0x630 but task is already holding lock: ffffffffafa1c0e8 (cpuidle_lock){+.+.}-{3:3}, at: cpuidle_pause_and_lock+0x17/0x20 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x3e/0xc0 irq_calc_affinity_vectors+0x5f/0x91 __pci_enable_msix_range+0x10f/0x9a0 pci_alloc_irq_vectors_affinity+0x13e/0x1f0 pci_alloc_irq_vectors_affinity at drivers/pci/msi.c:1208 pqi_ctrl_init+0x72f/0x1618 [smartpqi] pqi_pci_probe.cold.63+0x882/0x892 [smartpqi] local_pci_probe+0x7a/0xc0 work_for_cpu_fn+0x2e/0x50 process_one_work+0x57e/0xb90 worker_thread+0x363/0x5b0 kthread+0x1f4/0x220 ret_from_fork+0x27/0x50 -> #0 ((work_completion)(&wfc.work)){+.+.}-{0:0}: __lock_acquire+0x2244/0x32a0 lock_acquire+0x1a2/0x680 __flush_work+0x4e6/0x630 work_on_cpu+0x114/0x160 acpi_processor_ffh_cstate_probe+0x129/0x250 acpi_processor_evaluate_cst+0x4c8/0x580 acpi_processor_get_power_info+0x86/0x740 acpi_processor_hotplug+0xc3/0x140 acpi_soft_cpu_online+0x102/0x1d0 cpuhp_invoke_callback+0x197/0x1120 cpuhp_thread_fun+0x252/0x2f0 smpboot_thread_fn+0x255/0x440 kthread+0x1f4/0x220 ret_from_fork+0x27/0x50 other info that might help us debug this: Chain exists of: (work_completion)(&wfc.work) --> cpuhp_state-up --> cpuidle_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(cpuidle_lock); lock(cpuhp_state-up); lock(cpuidle_lock); lock((work_completion)(&wfc.work)); *** DEADLOCK *** 3 locks held by cpuhp/1/15: #0: ffffffffaf51ab10 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x69/0x2f0 #1: ffffffffaf51ad40 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x69/0x2f0 #2: ffffffffafa1c0e8 (cpuidle_lock){+.+.}-{3:3}, at: cpuidle_pause_and_lock+0x17/0x20 Call Trace: dump_stack+0xa0/0xea print_circular_bug.cold.52+0x147/0x14c check_noncircular+0x295/0x2d0 __lock_acquire+0x2244/0x32a0 lock_acquire+0x1a2/0x680 __flush_work+0x4e6/0x630 work_on_cpu+0x114/0x160 acpi_processor_ffh_cstate_probe+0x129/0x250 acpi_processor_evaluate_cst+0x4c8/0x580 acpi_processor_get_power_info+0x86/0x740 acpi_processor_hotplug+0xc3/0x140 acpi_soft_cpu_online+0x102/0x1d0 cpuhp_invoke_callback+0x197/0x1120 cpuhp_thread_fun+0x252/0x2f0 smpboot_thread_fn+0x255/0x440 kthread+0x1f4/0x220 ret_from_fork+0x27/0x50 Signed-off-by: Qian Cai <cai@lca.pw> Tested-by: Borislav Petkov <bp@suse.de> [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-04Merge tag 'perf-urgent-for-mingo-5.7-20200403' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Pull perf/urgent fixes and improvements from Arnaldo Carvalho de Melo: perf python: Arnaldo Carvalho de Melo: - Fix clang detection to strip out options passed in $CC. build: He Zhe: - Normalize gcc parameter when generating arch errno table, fixing the build by removing options from $(CC). Sam Lunt: - Support Python 3.8+ in Makefile. perf report/top: Arnaldo Carvalho de Melo: - Fix title line formatting. perf script: Andreas Gerstmayr: - Fix SEGFAULT when using DWARF mode. - Fix invalid read of directory entry after closedir(), found with valgrind. Hagen Paul Pfeifer: - Introduce --deltatime option. Stephane Eranian: - Allow --symbol to accept hexadecimal addresses. Ian Rogers: - Add -S/--symbols documentation Namhyung Kim: - Add --show-cgroup-events option. perf python: Arnaldo Carvalho de Melo: - Include rwsem.c in the python binding, needed by the cgroups improvements. build-test: Arnaldo Carvalho de Melo: - Honour JOBS to override detection of number of cores perf top: Jin Yao: - Support --group-sort-idx to change the sort order - perf top: Support hotkey to change sort order perf pmu-events x86: Jin Yao: - Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric perf symbols arm64: Kemeng Shi: - Fix arm64 gap between kernel start and module end kernel perf subsystem: Namhyung Kim: - Add PERF_RECORD_CGROUP event and Add PERF_SAMPLE_CGROUP feature, to allow cgroup tracking, saving a link between cgroup path and its id number. perf cgroup: Namhyung Kim: - Maintain cgroup hierarchy. perf report: Namhyung Kim: - Add 'cgroup' sort key. perf record: Namhyung Kim: - Support synthesizing cgroup events for pre-existing cgroups. - Add --all-cgroups option Documentation: Tony Jones: - Update docs regarding kernel/user space unwinding. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>