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2019-09-18Merge tag 'usb-5.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB updates from Greg KH: "Here is the big set of USB patches for 5.4-rc1. Two major chunks of code are moving out of the tree and into the staging directory, uwb and wusb (wireless USB support), because there are no devices that actually use this protocol anymore, and what we have today probably doesn't work at all given that the maintainers left many many years ago. So move it to staging where it will be removed in a few releases if no one screams. Other than that, lots of little things. The usual gadget and xhci and usb serial driver updates, along with a bunch of sysfs file cleanups due to the driver core changes to support that. Nothing really major, just constant forward progress. All of these have been in linux-next for a while with no reported issues" * tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (159 commits) USB: usbcore: Fix slab-out-of-bounds bug during device reset usb: cdns3: Remove redundant dev_err call in cdns3_probe() USB: rio500: Fix lockdep violation USB: rio500: simplify locking usb: mtu3: register a USB Role Switch for dual role mode usb: common: add USB GPIO based connection detection driver usb: common: create Kconfig file usb: roles: get usb-role-switch from parent usb: roles: Add fwnode_usb_role_switch_get() function device connection: Add fwnode_connection_find_match() usb: roles: Introduce stubs for the exiting functions in role.h dt-bindings: usb: mtu3: add properties about USB Role Switch dt-bindings: usb: add binding for USB GPIO based connection detection driver dt-bindings: connector: add optional properties for Type-B dt-binding: usb: add usb-role-switch property usbip: Implement SG support to vhci-hcd and stub driver usb: roles: intel: Enable static DRD mode for role switch xhci-ext-caps.c: Add property to disable Intel SW switch usb: dwc3: remove generic PHY calibrate() calls usb: core: phy: add support for PHY calibration ...
2019-09-18powerpc: Use ftrace_graph_ret_addr() when unwindingNaveen N. Rao
With support for HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, ftrace_graph_ret_addr() provides more robust unwinding when function graph is in use. Update show_stack() to use the same. With dump_stack() added to sysrq_sysctl_handler(), before this patch: root@(none):/sys/kernel/debug/tracing# cat /proc/sys/kernel/sysrq CPU: 0 PID: 218 Comm: cat Not tainted 5.3.0-rc7-00868-g8453ad4a078c-dirty #20 Call Trace: [c0000000d1e13c30] [c00000000006ab98] return_to_handler+0x0/0x40 (dump_stack+0xe8/0x164) (unreliable) [c0000000d1e13c80] [c000000000145680] sysrq_sysctl_handler+0x48/0xb8 [c0000000d1e13cd0] [c00000000006ab98] return_to_handler+0x0/0x40 (proc_sys_call_handler+0x274/0x2a0) [c0000000d1e13d60] [c00000000006ab98] return_to_handler+0x0/0x40 (return_to_handler+0x0/0x40) [c0000000d1e13d80] [c00000000006ab98] return_to_handler+0x0/0x40 (__vfs_read+0x3c/0x70) [c0000000d1e13dd0] [c00000000006ab98] return_to_handler+0x0/0x40 (vfs_read+0xb8/0x1b0) [c0000000d1e13e20] [c00000000006ab98] return_to_handler+0x0/0x40 (ksys_read+0x7c/0x140) After this patch: Call Trace: [c0000000d1e33c30] [c00000000006ab58] return_to_handler+0x0/0x40 (dump_stack+0xe8/0x164) (unreliable) [c0000000d1e33c80] [c000000000145680] sysrq_sysctl_handler+0x48/0xb8 [c0000000d1e33cd0] [c00000000006ab58] return_to_handler+0x0/0x40 (proc_sys_call_handler+0x274/0x2a0) [c0000000d1e33d60] [c00000000006ab58] return_to_handler+0x0/0x40 (__vfs_read+0x3c/0x70) [c0000000d1e33d80] [c00000000006ab58] return_to_handler+0x0/0x40 (vfs_read+0xb8/0x1b0) [c0000000d1e33dd0] [c00000000006ab58] return_to_handler+0x0/0x40 (ksys_read+0x7c/0x140) [c0000000d1e33e20] [c00000000006ab58] return_to_handler+0x0/0x40 (system_call+0x5c/0x68) Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/dc89c9a887121342d9c7819482c3dabdece2a323.1567707399.git.naveen.n.rao@linux.vnet.ibm.com
2019-09-18powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTRNaveen N. Rao
This associates entries in the ftrace_ret_stack with corresponding stack frames, enabling more robust stack unwinding. Also update the only user of ftrace_graph_ret_addr() to pass the stack pointer. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/0224f2d0971b069c678e2ff678cfc2cd1e114cfe.1567707399.git.naveen.n.rao@linux.vnet.ibm.com
2019-09-18powerpc: dump kernel log before carrying out fadump or kdumpGanesh Goudar
Since commit 4388c9b3a6ee ("powerpc: Do not send system reset request through the oops path"), pstore dmesg file is not updated when dump is triggered from HMC. This commit modified system reset (sreset) handler to invoke fadump or kdump (if configured), without pushing dmesg to pstore. This leaves pstore to have old dmesg data which won't be much of a help if kdump fails to capture the dump. This patch fixes that by calling kmsg_dump() before heading to fadump ot kdump. Fixes: 4388c9b3a6ee ("powerpc: Do not send system reset request through the oops path") Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190904075949.15607-1-ganeshgr@linux.ibm.com
2019-09-16Merge branch 'parisc-5.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux Pull parisc updates from Helge Deller: - Make the powerpc implementation to read elf files available as a public kexec interface so it can be re-used on other architectures (Sven) - Implement kexec on parisc (Sven) - Add kprobes on ftrace on parisc (Sven) - Fix kernel crash with HSC-PCI cards based on card-mode Dino - Add assembly implementations for memset, strlen, strcpy, strncpy and strcat - Some cleanups, documentation updates, warning fixes, ... * 'parisc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (25 commits) parisc: Have git ignore generated real2.S and firmware.c parisc: Disable HP HSC-PCI Cards to prevent kernel crash parisc: add support for kexec_file_load() syscall parisc: wire up kexec_file_load syscall parisc: add kexec syscall support parisc: add __pdc_cpu_rendezvous() kprobes/parisc: remove arch_kprobe_on_func_entry() kexec_elf: support 32 bit ELF files kexec_elf: remove unused variable in kexec_elf_load() kexec_elf: remove Elf_Rel macro kexec_elf: remove PURGATORY_STACK_SIZE kexec_elf: remove parsing of section headers kexec_elf: change order of elf_*_to_cpu() functions kexec: add KEXEC_ELF parisc: Save some bytes in dino driver parisc: Drop comments which are already in pci.h parisc: Convert eisa_enumerator to use pr_cont() parisc: Avoid warning when loading hppb driver parisc: speed up flush_tlb_all_local with qemu parisc: Add ALTERNATIVE_CODE() and ALT_COND_RUN_ON_QEMU ...
2019-09-14powerpc/fadump: support holes in kernel boot memory areaHari Bathini
With support to copy multiple kernel boot memory regions owing to copy size limitation, also handle holes in the memory area to be preserved. Support as many as 128 kernel boot memory regions. This allows having an adequate FADump capture kernel size for different scenarios. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821385448.5656.6124791213910877759.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: remove RMA_START and RMA_END macrosHari Bathini
RMA_START is defined as '0' and there is even a BUILD_BUG_ON() to make sure it is never anything else. Remove this macro and use '0' instead as code change is needed anyway when it has to be something else. Also, remove unused RMA_END macro. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821384096.5656.15026984053970204652.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: consider f/w load areaHari Bathini
OPAL loads kernel & initrd at 512MB offset (256MB size), also exported as ibm,opal/dump/fw-load-area. So, if boot memory size of FADump is less than 768MB, kernel memory to be exported as '/proc/vmcore' would be overwritten by f/w while loading kernel & initrd. To avoid such a scenario, enforce a minimum boot memory size of 768MB on OPAL platform and skip using FADump if a newer F/W version loads kernel & initrd above 768MB. Also, irrespective of RMA size, set the minimum boot memory size expected on pseries platform at 320MB. This is to avoid inflating the minimum memory requirements on systems with 512M/1024M RMA size. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821381414.5656.1592867278535469652.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: add support to preserve crash data on FADUMP disabled kernelHari Bathini
Add a new kernel config option, CONFIG_PRESERVE_FA_DUMP that ensures that crash data, from previously crash'ed kernel, is preserved. This helps in cases where FADump is not enabled but the subsequent memory preserving kernel boot is likely to process this crash data. One typical usecase for this config option is petitboot kernel. As OPAL allows registering address with it in the first kernel and retrieving it after MPIPL, use it to store the top of boot memory. A kernel that intends to preserve crash data retrieves it and avoids using memory beyond this address. Move arch_reserved_kernel_pages() function as it is needed for both FA_DUMP and PRESERVE_FA_DUMP configurations. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821375751.5656.11459483669542541602.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: improve how crashed kernel's memory is reservedHari Bathini
The size parameter to fadump_reserve_crash_area() function is not needed as all the memory above boot memory size must be preserved anyway. Update the function by dropping this redundant parameter. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821374440.5656.2945512543806951766.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: consider reserved ranges while releasing memoryHari Bathini
Commit 0962e8004e97 ("powerpc/prom: Scan reserved-ranges node for memory reservations") enabled support to parse 'reserved-ranges' DT node to reserve kernel memory falling in these ranges for firmware purposes. Along with the preserved area memory, ensure memory in reserved ranges is not overlapped with memory released by capture kernel aftering saving vmcore. Also, fix the off-by-one error in fadump_release_reserved_area function while releasing memory. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821371358.5656.6061214942558818661.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: make crash memory ranges array allocation genericHari Bathini
Make allocate_crash_memory_ranges() and free_crash_memory_ranges() functions generic to reuse them for memory management of all types of dynamic memory range arrays. This change helps in memory management of reserved ranges array to be added later. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821369863.5656.4375667005352155892.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: make use of memblock's bottom up allocation modeHari Bathini
Earlier, memblock_find_in_range() was not used to find the memory to be reserved for FADump as bottom up allocation mode was not supported. But since commit 79442ed189acb8b ("mm/memblock.c: introduce bottom-up allocation mode") bottom up allocation mode is supported for memblock. So, use it to find the memory to be reserved for FADump. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821364211.5656.14336025460336135194.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: handle invalidation of crashdump and re-registraionHari Bathini
Make OPAL call to indicate that the dump is processed and the metadata area in OPAL can be cleared/released. Also, setup/initialize FADump for re-registration. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821356046.5656.12270927048195494911.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: reset metadata address during clean upHari Bathini
During kexec boot, metadata address needs to be reset to avoid running into errors interpreting stale metadata address, in case the kexec'ed kernel crashes before metadata address could be setup again. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821346629.5656.10783321582005237813.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: register kernel metadata address with opalHari Bathini
OPAL allows registering address with it in the first kernel and retrieving it after MPIPL. Setup kernel metadata and register its address with OPAL to use it for processing the crash dump. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821345011.5656.13567765019032928471.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: improve fadump_reserve_mem()Hari Bathini
Some code clean-up like using minimal assignments and updating printk messages. Also, add an 'error_out' label for handling error cleanup at one place. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821343485.5656.10202857091553646948.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: add fadump support on powernvHari Bathini
Add basic callback functions for FADump on PowerNV platform. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821342072.5656.4346362203141486452.stgit@hbathini.in.ibm.com
2019-09-14pseries/fadump: move out platform specific support from generic codeHari Bathini
Move code that supports processing the crash'ed kernel's memory preserved by firmware to platform specific callback functions. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821337690.5656.13050665924800177744.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: release all the memory above boot memory sizeHari Bathini
Except for Reserved dump area (see Documentation/powerpc/firmware- assisted-dump.rst) which is permanent reserved, all memory above boot memory size, where boot memory size is the memory required for the kernel to boot successfully when booted with restricted memory (memory for capture kernel), is released when the dump is invalidated. Make this a bit more explicit in the code. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821336092.5656.1079046285366041687.stgit@hbathini.in.ibm.com
2019-09-14pseries/fadump: define RTAS register/un-register callback functionsHari Bathini
Move platform specific register/un-register code, the RTAS calls, to register/un-register callback functions. This would also mean moving code that initializes and prints the platform specific FADump data. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821332856.5656.16380417702046411631.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: introduce callbacks for platform specific operationsHari Bathini
Introduce callback functions for platform specific operations like register, unregister, invalidate & such. Also, define place-holders for the same on pSeries platform. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821330286.5656.15538934400074110770.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: move rtas specific definitions to platform codeHari Bathini
Currently, FADump is only supported on pSeries but that is going to change soon with FADump support being added on PowerNV platform. So, move rtas specific definitions to platform code to allow FADump to have multiple platforms support. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821328494.5656.16219929140866195511.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: use helper functions to reserve/release cpu notes bufferHari Bathini
Use helper functions to simplify memory allocation, pinning down and freeing the memory used for CPU notes buffer. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821323555.5656.2486038022572739622.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: declare helper functions in internal header fileHari Bathini
Declare helper functions, that can be reused by multiple platforms, in the internal header file. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821320487.5656.2660730464212209984.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: add helper functionsHari Bathini
Add helper functions to setup & free CPU notes buffer and to find if a given memory area is contiguous. Also, use boolean as return type for the function that finds if boot memory area is contiguous. While at it, save the virtual address of CPU notes buffer instead of physical address as virtual address is used often. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821318971.5656.9281936950510635858.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: move internal macros/definitions to a new headerHari Bathini
Though asm/fadump.h is meant to be used by other components dealing with FADump, it also has macros/definitions internal to FADump code. Move them to a new header file used within FADump code. This also makes way for refactoring platform specific FADump code. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821313134.5656.6597770626574392140.stgit@hbathini.in.ibm.com
2019-09-14powerpc: improve prom_init_check ruleMasahiro Yamada
This slightly improves the prom_init_check rule. [1] Avoid needless check Currently, prom_init_check.sh is invoked every time you run 'make' even if you have changed nothing in prom_init.c. With this commit, the script is re-run only when prom_init.o is recompiled. [2] Beautify the build log Currently, the O= build shows the absolute path to the script: CALL /abs/path/to/source/of/linux/arch/powerpc/kernel/prom_init_check.sh With this commit, it is always a relative path to the timestamp file: PROMCHK arch/powerpc/kernel/prom_init_check Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190912074037.13813-1-yamada.masahiro@socionext.com
2019-09-14powerpc/kvm: Add ifdefs around template codeMichael Ellerman
Some of the templates used for KVM patching are only used on certain platforms, but currently they are always built-in, fix that. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911115746.12433-4-mpe@ellerman.id.au
2019-09-14powerpc/kvm: Explicitly mark kvm guest code as __initMichael Ellerman
All the code in kvm.c can be marked __init. Most of it is already inlined into the initcall, but not all. So instead of relying on the inlining, mark it all as __init. This saves ~280 bytes of text for my configuration. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911115746.12433-3-mpe@ellerman.id.au
2019-09-14powerpc/kvm: Move kvm_tmp into .text, shrink to 64KMichael Ellerman
In some configurations of KVM, guests binary patch themselves to avoid/reduce trapping into the hypervisor. For some instructions this requires replacing one instruction with a sequence of instructions. For those cases we need to write the sequence of instructions somewhere and then patch the location of the original instruction to branch to the sequence. That requires that the location of the sequence be within 32MB of the original instruction. The current solution for this is that we create a 1MB array in BSS, write sequences into there, and then free the remainder of the array. This has a few problems: - it confuses kmemleak. - it confuses lockdep. - it requires mapping kvm_tmp executable, which can cause adjacent areas to also be mapped executable if we're using 16M pages for the linear mapping. - the 32MB limit can be exceeded if the kernel is big enough, especially with STRICT_KERNEL_RWX enabled, which then prevents the patching from working at all. We can fix all those problems by making kvm_tmp just a region of regular .text. However currently it's 1MB in size, and we don't want to waste 1MB of text. In practice however I only see ~30KB of kvm_tmp being used even for an allyes_config. So shrink kvm_tmp to 64K, which ought to be enough for everyone, and move it into .text. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911115746.12433-1-mpe@ellerman.id.au
2019-09-14powerpc/eeh: Fix build with STACKTRACE=nMichael Ellerman
The build breaks when STACKTRACE=n, eg. skiroot_defconfig: arch/powerpc/kernel/eeh_event.c:124:23: error: implicit declaration of function 'stack_trace_save' Fix it with some ifdefs for now. Fixes: 25baf3d81614 ("powerpc/eeh: Defer printing stack trace") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-09-12powerpc/watchpoint: Disable watchpoint hit by larx/stcx instructionsRavi Bangoria
If watchpoint exception is generated by larx/stcx instructions, the reservation created by larx gets lost while handling exception, and thus stcx instruction always fails. Generally these instructions are used in a while(1) loop, for example spinlocks. And because stcx never succeeds, it loops forever and ultimately hangs the system. Note that ptrace anyway works in one-shot mode and thus for ptrace we don't change the behaviour. It's up to ptrace user to take care of this. Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190910131513.30499-1-ravi.bangoria@linux.ibm.com
2019-09-06kexec: add KEXEC_ELFSven Schnelle
Right now powerpc provides an implementation to read elf files with the kexec_file_load() syscall. Make that available as a public kexec interface so it can be re-used on other architectures. Signed-off-by: Sven Schnelle <svens@stackframe.org> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Helge Deller <deller@gmx.de>
2019-09-06Merge tag 'powerpc-5.3-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "One fix for a boot hang on some Freescale machines when PREEMPT is enabled. Two CVE fixes for bugs in our handling of FP registers and transactional memory, both of which can result in corrupted FP state, or FP state leaking between processes. Thanks to: Chris Packham, Christophe Leroy, Gustavo Romero, Michael Neuling" * tag 'powerpc-5.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/tm: Fix restoring FP/VMX facility incorrectly on interrupts powerpc/tm: Fix FP/VMX unavailable exceptions inside a transaction powerpc/64e: Drop stale call to smp_processor_id() which hangs SMP startup
2019-09-05powerpc/eeh: Add a eeh_dev_break debugfs interfaceOliver O'Halloran
Add an interface to debugfs for generating an EEH event on a given device. This works by disabling memory accesses to and from the device by setting the PCI_COMMAND register (or the VF Memory Space Enable on the parent PF). This is a somewhat portable alternative to using the platform specific error injection mechanisms since those tend to be either hard to use, or straight up broken. For pseries the interfaces also requires the use of /dev/mem which is probably going to go away in a post-LOCKDOWN world (and it's a horrific hack to begin with) so moving to a kernel-provided interface makes sense and provides a sane, cross-platform interface for userspace so we can write more generic testing scripts. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-14-oohall@gmail.com
2019-09-05powerpc/eeh: Add debugfs interface to run an EEH checkOliver O'Halloran
Detecting an frozen EEH PE usually occurs when an MMIO load returns a 0xFFs response. When performing EEH testing using the EEH error injection feature available on some platforms there is no simple way to kick-off the kernel's recovery process since any accesses from userspace (usually /dev/mem) will bypass the MMIO helpers in the kernel which check if a 0xFF response is due to an EEH freeze or not. If a device contains a 0xFF byte in it's config space it's possible to trigger the recovery process via config space read from userspace, but this is not a reliable method. If a driver is bound to the device an in use it will frequently trigger the MMIO check, but this is also inconsistent. To solve these problems this patch adds a debugfs file called "eeh_dev_check" which accepts a <domain>:<bus>:<dev>.<fn> string and runs eeh_dev_check_failure() on it. This is the same check that's done when the kernel gets a 0xFF result from an config or MMIO read with the added benifit that it can be reliably triggered from userspace. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-13-oohall@gmail.com
2019-09-05powerpc/eeh: Set attention indicator while recoveringOliver O'Halloran
I am the RAS team. Hear me roar. Roar. On a more serious note, being able to locate failed devices can be helpful. Set the attention indicator if the slot supports it once we've determined the device is present and only clear it if the device is fully recovered. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-12-oohall@gmail.com
2019-09-05powerpc/eeh: Defer printing stack traceOliver O'Halloran
Currently we print a stack trace in the event handler to help with debugging EEH issues. In the case of suprise hot-unplug this is unneeded, so we want to prevent printing the stack trace unless we know it's due to an actual device error. To accomplish this, we can save a stack trace at the point of detection and only print it once the EEH recovery handler has determined the freeze was due to an actual error. Since the whole point of this is to prevent spurious EEH output we also move a few prints out of the detection thread, or mark them as pr_debug so anyone interested can get output from the eeh_check_dev_failure() if they want. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-6-oohall@gmail.com
2019-09-05powerpc/eeh: Check slot presence state in eeh_handle_normal_event()Oliver O'Halloran
When a device is surprise removed while undergoing IO we will probably get an EEH PE freeze due to MMIO timeouts and other errors. When a freeze is detected we send a recovery event to the EEH worker thread which will notify drivers, and perform recovery as needed. In the event of a hot-remove we don't want recovery to occur since there isn't a device to recover. The recovery process is fairly long due to the number of wait states (required by PCIe) which causes problems when devices are removed and replaced (e.g. hot swapping of U.2 NVMe drives). To determine if we need to skip the recovery process we can use the get_adapter_state() operation of the hotplug_slot to determine if the slot contains a device or not, and if the slot is empty we can skip recovery entirely. One thing to note is that the slot being EEH frozen does not prevent the hotplug driver from working. We don't have the EEH recovery thread remove any of the devices since it's assumed that the hotplug driver will handle tearing down the slot state. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-5-oohall@gmail.com
2019-09-05powerpc/eeh: Make permanently failed devices non-actionableOliver O'Halloran
If a device is torn down by a hotplug slot driver it's marked as removed and marked as permaantly failed. There's no point in trying to recover a permernantly failed device so it should be considered un-actionable. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-4-oohall@gmail.com
2019-09-05powerpc/eeh: Fix race when freeing PDNsOliver O'Halloran
When hot-adding devices we rely on the hotplug driver to create pci_dn's for the devices under the hotplug slot. Converse, when hot-removing the driver will remove the pci_dn's that it created. This is a problem because the pci_dev is still live until it's refcount drops to zero. This can happen if the driver is slow to tear down it's internal state. Ideally, the driver would not attempt to perform any config accesses to the device once it's been marked as removed, but sometimes it happens. As a result, we might attempt to access the pci_dn for a device that has been torn down and the kernel may crash as a result. To fix this, don't free the pci_dn unless the corresponding pci_dev has been released. If the pci_dev is still live, then we mark the pci_dn with a flag that indicates the pci_dev's release function should free it. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-3-oohall@gmail.com
2019-09-05powerpc/eeh: Clean up EEH PEs after recovery finishesOliver O'Halloran
When the last device in an eeh_pe is removed the eeh_pe structure itself (and any empty parents) are freed since they are no longer needed. This results in a crash when a hotplug driver is involved since the following may occur: 1. Device is suprise removed. 2. Driver performs an MMIO, which fails and queues and eeh_event. 3. Hotplug driver receives a hotplug interrupt and removes any pci_devs that were under the slot. 4. pci_dev is torn down and the eeh_pe is freed. 5. The EEH event handler thread processes the eeh_event and crashes since the eeh_pe pointer in the eeh_event structure is no longer valid. Crashing is generally considered poor form. Instead of doing that use the fact PEs are marked as EEH_PE_INVALID to keep them around until the end of the recovery cycle, at which point we can safely prune any empty PEs. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-2-oohall@gmail.com
2019-09-04kbuild: add $(BASH) to run scripts with bash-extensionMasahiro Yamada
CONFIG_SHELL falls back to sh when bash is not installed on the system, but nobody is testing such a case since bash is usually installed. So, shell scripts invoked by CONFIG_SHELL are only tested with bash. It makes it difficult to test whether the hashbang #!/bin/sh is real. For example, #!/bin/sh in arch/powerpc/kernel/prom_init_check.sh is false. (I fixed it up) Besides, some shell scripts invoked by CONFIG_SHELL use bash-extension and #!/bin/bash is specified as the hashbang, while CONFIG_SHELL may not always be set to bash. Probably, the right thing to do is to introduce BASH, which is bash by default, and always set CONFIG_SHELL to sh. Replace $(CONFIG_SHELL) with $(BASH) for bash scripts. If somebody tries to add bash-extension to a #!/bin/sh script, it will be caught in testing because /bin/sh is a symlink to dash on some major distributions. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-09-04powerpc/tm: Fix restoring FP/VMX facility incorrectly on interruptsGustavo Romero
When in userspace and MSR FP=0 the hardware FP state is unrelated to the current process. This is extended for transactions where if tbegin is run with FP=0, the hardware checkpoint FP state will also be unrelated to the current process. Due to this, we need to ensure this hardware checkpoint is updated with the correct state before we enable FP for this process. Unfortunately we get this wrong when returning to a process from a hardware interrupt. A process that starts a transaction with FP=0 can take an interrupt. When the kernel returns back to that process, we change to FP=1 but with hardware checkpoint FP state not updated. If this transaction is then rolled back, the FP registers now contain the wrong state. The process looks like this: Userspace: Kernel Start userspace with MSR FP=0 TM=1 < ----- ... tbegin bne Hardware interrupt ---- > <do_IRQ...> .... ret_from_except restore_math() /* sees FP=0 */ restore_fp() tm_active_with_fp() /* sees FP=1 (Incorrect) */ load_fp_state() FP = 0 -> 1 < ----- Return to userspace with MSR TM=1 FP=1 with junk in the FP TM checkpoint TM rollback reads FP junk When returning from the hardware exception, tm_active_with_fp() is incorrectly making restore_fp() call load_fp_state() which is setting FP=1. The fix is to remove tm_active_with_fp(). tm_active_with_fp() is attempting to handle the case where FP state has been changed inside a transaction. In this case the checkpointed and transactional FP state is different and hence we must restore the FP state (ie. we can't do lazy FP restore inside a transaction that's used FP). It's safe to remove tm_active_with_fp() as this case is handled by restore_tm_state(). restore_tm_state() detects if FP has been using inside a transaction and will set load_fp and call restore_math() to ensure the FP state (checkpoint and transaction) is restored. This is a data integrity problem for the current process as the FP registers are corrupted. It's also a security problem as the FP registers from one process may be leaked to another. Similarly for VMX. A simple testcase to replicate this will be posted to tools/testing/selftests/powerpc/tm/tm-poison.c This fixes CVE-2019-15031. Fixes: a7771176b439 ("powerpc: Don't enable FP/Altivec if not checkpointed") Cc: stable@vger.kernel.org # 4.15+ Signed-off-by: Gustavo Romero <gromero@linux.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190904045529.23002-2-gromero@linux.vnet.ibm.com
2019-09-04powerpc/tm: Fix FP/VMX unavailable exceptions inside a transactionGustavo Romero
When we take an FP unavailable exception in a transaction we have to account for the hardware FP TM checkpointed registers being incorrect. In this case for this process we know the current and checkpointed FP registers must be the same (since FP wasn't used inside the transaction) hence in the thread_struct we copy the current FP registers to the checkpointed ones. This copy is done in tm_reclaim_thread(). We use thread->ckpt_regs.msr to determine if FP was on when in userspace. thread->ckpt_regs.msr represents the state of the MSR when exiting userspace. This is setup by check_if_tm_restore_required(). Unfortunatley there is an optimisation in giveup_all() which returns early if tsk->thread.regs->msr (via local variable `usermsr`) has FP=VEC=VSX=SPE=0. This optimisation means that check_if_tm_restore_required() is not called and hence thread->ckpt_regs.msr is not updated and will contain an old value. This can happen if due to load_fp=255 we start a userspace process with MSR FP=1 and then we are context switched out. In this case thread->ckpt_regs.msr will contain FP=1. If that same process is then context switched in and load_fp overflows, MSR will have FP=0. If that process now enters a transaction and does an FP instruction, the FP unavailable will not update thread->ckpt_regs.msr (the bug) and MSR FP=1 will be retained in thread->ckpt_regs.msr. tm_reclaim_thread() will then not perform the required memcpy and the checkpointed FP regs in the thread struct will contain the wrong values. The code path for this happening is: Userspace: Kernel Start userspace with MSR FP/VEC/VSX/SPE=0 TM=1 < ----- ... tbegin bne fp instruction FP unavailable ---- > fp_unavailable_tm() tm_reclaim_current() tm_reclaim_thread() giveup_all() return early since FP/VMX/VSX=0 /* ckpt MSR not updated (Incorrect) */ tm_reclaim() /* thread_struct ckpt FP regs contain junk (OK) */ /* Sees ckpt MSR FP=1 (Incorrect) */ no memcpy() performed /* thread_struct ckpt FP regs not fixed (Incorrect) */ tm_recheckpoint() /* Put junk in hardware checkpoint FP regs */ .... < ----- Return to userspace with MSR TM=1 FP=1 with junk in the FP TM checkpoint TM rollback reads FP junk This is a data integrity problem for the current process as the FP registers are corrupted. It's also a security problem as the FP registers from one process may be leaked to another. This patch moves up check_if_tm_restore_required() in giveup_all() to ensure thread->ckpt_regs.msr is updated correctly. A simple testcase to replicate this will be posted to tools/testing/selftests/powerpc/tm/tm-poison.c Similarly for VMX. This fixes CVE-2019-15030. Fixes: f48e91e87e67 ("powerpc/tm: Fix FP and VMX register corruption") Cc: stable@vger.kernel.org # 4.12+ Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190904045529.23002-1-gromero@linux.vnet.ibm.com
2019-09-04dma-mapping: explicitly wire up ->mmap and ->get_sgtableChristoph Hellwig
While the default ->mmap and ->get_sgtable implementations work for the majority of our dma_map_ops impementations they are inherently safe for others that don't use the page allocator or CMA and/or use their own way of remapping not covered by the common code. So remove the defaults if these methods are not wired up, but instead wire up the default implementations for all safe instances. Fixes: e1c7e324539a ("dma-mapping: always provide the dma_map_ops based implementation") Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-08-30powerpc/64s/exception: reduce page fault unnecessary loadsNicholas Piggin
This avoids 3 loads in the radix page fault case, 1 load in the hash fault case, and 2 loads in the hash miss page fault case. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-37-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Remove pointless KVM handler name bifurcationNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-36-npiggin@gmail.com
2019-08-30powerpc/64s/exception: program check handler do not branch into a macroNicholas Piggin
It is clever, but the small code saving is not worth the spaghetti of jumping to a label in an expanded macro, particularly when the label is just a number rather than a descriptive name. So expand the INT_COMMON macro twice, once for the stack and no stack cases, and branch to those. The slight code size increase is worth the improved clarity of branches for this non-performance critical code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-35-npiggin@gmail.com