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2022-05-27Merge tag 'mm-nonmm-stable-2022-05-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc updates from Andrew Morton: "The non-MM patch queue for this merge window. Not a lot of material this cycle. Many singleton patches against various subsystems. Most notably some maintenance work in ocfs2 and initramfs" * tag 'mm-nonmm-stable-2022-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (65 commits) kcov: update pos before writing pc in trace function ocfs2: dlmfs: fix error handling of user_dlm_destroy_lock ocfs2: dlmfs: don't clear USER_LOCK_ATTACHED when destroying lock fs/ntfs: remove redundant variable idx fat: remove time truncations in vfat_create/vfat_mkdir fat: report creation time in statx fat: ignore ctime updates, and keep ctime identical to mtime in memory fat: split fat_truncate_time() into separate functions MAINTAINERS: add Muchun as a memcg reviewer proc/sysctl: make protected_* world readable ia64: mca: drop redundant spinlock initialization tty: fix deadlock caused by calling printk() under tty_port->lock relay: remove redundant assignment to pointer buf fs/ntfs3: validate BOOT sectors_per_clusters lib/string_helpers: fix not adding strarray to device's resource list kernel/crash_core.c: remove redundant check of ck_cmdline ELF, uapi: fixup ELF_ST_TYPE definition ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() ipc: update semtimedop() to use hrtimer ipc/sem: remove redundant assignments ...
2022-05-26Merge tag 'sysctl-5.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "For two kernel releases now kernel/sysctl.c has been being cleaned up slowly, since the tables were grossly long, sprinkled with tons of #ifdefs and all this caused merge conflicts with one susbystem or another. This tree was put together to help try to avoid conflicts with these cleanups going on different trees at time. So nothing exciting on this pull request, just cleanups. Thanks a lot to the Uniontech and Huawei folks for doing some of this nasty work" * tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (28 commits) sched: Fix build warning without CONFIG_SYSCTL reboot: Fix build warning without CONFIG_SYSCTL kernel/kexec_core: move kexec_core sysctls into its own file sysctl: minor cleanup in new_dir() ftrace: fix building with SYSCTL=y but DYNAMIC_FTRACE=n fs/proc: Introduce list_for_each_table_entry for proc sysctl mm: fix unused variable kernel warning when SYSCTL=n latencytop: move sysctl to its own file ftrace: fix building with SYSCTL=n but DYNAMIC_FTRACE=y ftrace: Fix build warning ftrace: move sysctl_ftrace_enabled to ftrace.c kernel/do_mount_initrd: move real_root_dev sysctls to its own file kernel/delayacct: move delayacct sysctls to its own file kernel/acct: move acct sysctls to its own file kernel/panic: move panic sysctls to its own file kernel/lockdep: move lockdep sysctls to its own file mm: move page-writeback sysctls to their own file mm: move oom_kill sysctls to their own file kernel/reboot: move reboot sysctls to its own file sched: Move energy_aware sysctls to topology.c ...
2022-04-29kexec: remove redundant assignmentsMichal Orzel
Get rid of redundant assignments which end up in values not being read either because they are overwritten or the function ends. Reported by clang-tidy [deadcode.DeadStores] Link: https://lkml.kernel.org/r/20220326180948.192154-1-michalorzel.eng@gmail.com Signed-off-by: Michal Orzel <michalorzel.eng@gmail.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Michal Orzel <michalorzel.eng@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-25kernel/kexec_core: move kexec_core sysctls into its own fileyingelin
This move the kernel/kexec_core.c respective sysctls to its own file. kernel/sysctl.c has grown to an insane mess, We move sysctls to places where features actually belong to improve the readability and reduce merge conflicts. At the same time, the proc-sysctl maintainers can easily care about the core logic other than the sysctl knobs added for some feature. We already moved all filesystem sysctls out. This patch is part of the effort to move kexec related sysctls out. Signed-off-by: yingelin <yingelin@huawei.com> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-04-14ELF: Remove elf_core_copy_kernel_regs()Brian Gerst
x86-32 was the last architecture that implemented separate user and kernel registers. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220325153953.162643-3-brgerst@gmail.com
2021-12-13exit: Move oops specific logic from do_exit into make_task_deadEric W. Biederman
The beginning of do_exit has become cluttered and difficult to read as it is filled with checks to handle things that can only happen when the kernel is operating improperly. Now that we have a dedicated function for cleaning up a task when the kernel is operating improperly move the checks there. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-08-30Merge branch 'rework/printk_safe-removal' into for-linusPetr Mladek
2021-07-26printk: remove safe buffersJohn Ogness
With @logbuf_lock removed, the high level printk functions for storing messages are lockless. Messages can be stored from any context, so there is no need for the NMI and safe buffers anymore. Remove the NMI and safe buffers. Although the safe buffers are removed, the NMI and safe context tracking is still in place. In these contexts, store the message immediately but still use irq_work to defer the console printing. Since printk recursion tracking is in place, safe context tracking for most of printk is not needed. Remove it. Only safe context tracking relating to the console and console_owner locks is left in place. This is because the console and console_owner locks are needed for the actual printing. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20210715193359.25946-4-john.ogness@linutronix.de
2021-07-01kernel.h: split out panic and oops helpersAndy Shevchenko
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out panic and oops helpers. There are several purposes of doing this: - dropping dependency in bug.h - dropping a loop by moving out panic_notifier.h - unload kernel.h from something which has its own domain At the same time convert users tree-wide to use new headers, although for the time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [akpm@linux-foundation.org: thread_info.h needs limits.h] [andriy.shevchenko@linux.intel.com: ia64 fix] Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Co-developed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Corey Minyard <cminyard@mvista.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Sebastian Reichel <sre@kernel.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kexec: dump kmessage before machine_kexecPavel Tatashin
kmsg_dump(KMSG_DUMP_SHUTDOWN) is called before machine_restart(), machine_halt(), and machine_power_off(). The only one that is missing is machine_kexec(). The dmesg output that it contains can be used to study the shutdown performance of both kernel and systemd during kexec reboot. Here is example of dmesg data collected after kexec: root@dplat-cp22:~# cat /sys/fs/pstore/dmesg-ramoops-0 | tail ... [ 70.914592] psci: CPU3 killed (polled 0 ms) [ 70.915705] CPU4: shutdown [ 70.916643] psci: CPU4 killed (polled 4 ms) [ 70.917715] CPU5: shutdown [ 70.918725] psci: CPU5 killed (polled 0 ms) [ 70.919704] CPU6: shutdown [ 70.920726] psci: CPU6 killed (polled 4 ms) [ 70.921642] CPU7: shutdown [ 70.922650] psci: CPU7 killed (polled 0 ms) Link: https://lkml.kernel.org/r/20210319192326.146000-2-pasha.tatashin@soleen.com Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: James Morris <jmorris@namei.org> Cc: Sasha Levin <sashal@kernel.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kexec: Add kexec reboot stringJoe LeVeque
The purpose is to notify the kernel module for fast reboot. Upstream a patch from the SONiC network operating system [1]. [1]: https://github.com/Azure/sonic-linux-kernel/pull/46 Link: https://lkml.kernel.org/r/20210304124626.13927-1-pmenzel@molgen.mpg.de Signed-off-by: Joe LeVeque <jolevequ@microsoft.com> Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de> Acked-by: Baoquan He <bhe@redhat.com> Cc: Guohan Lu <lguohan@gmail.com> Cc: Joe LeVeque <jolevequ@microsoft.com> Cc: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-21Merge branch 'work.elf-compat' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull ELF compat updates from Al Viro: "Sanitizing ELF compat support, especially for triarch architectures: - X32 handling cleaned up - MIPS64 uses compat_binfmt_elf.c both for O32 and N32 now - Kconfig side of things regularized Eventually I hope to have compat_binfmt_elf.c killed, with both native and compat built from fs/binfmt_elf.c, with -DELF_BITS={64,32} passed by kbuild, but that's a separate story - not included here" * 'work.elf-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: get rid of COMPAT_ELF_EXEC_PAGESIZE compat_binfmt_elf: don't bother with undef of ELF_ARCH Kconfig: regularize selection of CONFIG_BINFMT_ELF mips compat: switch to compat_binfmt_elf.c mips: don't bother with ELF_CORE_EFLAGS mips compat: don't bother with ELF_ET_DYN_BASE mips: KVM_GUEST makes no sense for 64bit builds... mips: kill unused definitions in binfmt_elf[on]32.c mips binfmt_elf*32.c: use elfcore-compat.h x32: make X32, !IA32_EMULATION setups able to execute x32 binaries [amd64] clean PRSTATUS_SIZE/SET_PR_FPVALID up properly elf_prstatus: collect the common part (everything before pr_reg) into a struct binfmt_elf: partially sanitize PRSTATUS_SIZE and SET_PR_FPVALID
2021-01-25kernel: kexec: remove the lock operation of system_transition_mutexBaoquan He
Function kernel_kexec() is called with lock system_transition_mutex held in reboot system call. While inside kernel_kexec(), it will acquire system_transition_mutex agin. This will lead to dead lock. The dead lock should be easily triggered, it hasn't caused any failure report just because the feature 'kexec jump' is almost not used by anyone as far as I know. An inquiry can be made about who is using 'kexec jump' and where it's used. Before that, let's simply remove the lock operation inside CONFIG_KEXEC_JUMP ifdeffery scope. Fixes: 55f2503c3b69 ("PM / reboot: Eliminate race between reboot and suspend") Signed-off-by: Baoquan He <bhe@redhat.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Pingfan Liu <kernelfans@gmail.com> Cc: 4.19+ <stable@vger.kernel.org> # 4.19+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-06elf_prstatus: collect the common part (everything before pr_reg) into a structAl Viro
Preparations to doing i386 compat elf_prstatus sanely - rather than duplicating the beginning of compat_elf_prstatus, take these fields into a separate structure (compat_elf_prstatus_common), so that it could be reused. Due to the incestous relationship between binfmt_elf.c and compat_binfmt_elf.c we need the same shape change done to native struct elf_prstatus, gathering the fields prior to pr_reg into a new structure (struct elf_prstatus_common). Fortunately, offset of pr_reg is always a multiple of 16 with no padding right before it, so it's possible to turn all the stuff prior to it into a single member without disturbing the layout. [build fix from Geert Uytterhoeven folded in] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-11-20crypto: sha - split sha.h into sha1.h and sha2.hEric Biggers
Currently <crypto/sha.h> contains declarations for both SHA-1 and SHA-2, and <crypto/sha3.h> contains declarations for SHA-3. This organization is inconsistent, but more importantly SHA-1 is no longer considered to be cryptographically secure. So to the extent possible, SHA-1 shouldn't be grouped together with any of the other SHA versions, and usage of it should be phased out. Therefore, split <crypto/sha.h> into two headers <crypto/sha1.h> and <crypto/sha2.h>, and make everyone explicitly specify whether they want the declarations for SHA-1, SHA-2, or both. This avoids making the SHA-1 declarations visible to files that don't want anything to do with SHA-1. It also prepares for potentially moving sha1.h into a new insecure/ or dangerous/ directory. Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-16kernel/: fix repeated words in commentsRandy Dunlap
Fix multiple occurrences of duplicated words in kernel/. Fix one typo/spello on the same line as a duplicate word. Change one instance of "the the" to "that the". Otherwise just drop one of the repeated words. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/98202fa6-8919-ef63-9efe-c0fad5ca7af1@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-10objtool: Rename frame.h -> objtool.hJulien Thierry
Header frame.h is getting more code annotations to help objtool analyze object files. Rename the file to objtool.h. [ jpoimboe: add objtool.h to MAINTAINERS ] Signed-off-by: Julien Thierry <jthierry@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2020-01-08kexec: add machine_kexec_post_load()Pavel Tatashin
It is the same as machine_kexec_prepare(), but is called after segments are loaded. This way, can do processing work with already loaded relocation segments. One such example is arm64: it has to have segments loaded in order to create a page table, but it cannot do it during kexec time, because at that time allocations won't be possible anymore. Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Will Deacon <will@kernel.org>
2020-01-08kexec: quiet down kexec rebootPavel Tatashin
Here is a regular kexec command sequence and output: ===== $ kexec --reuse-cmdline -i --load Image $ kexec -e [ 161.342002] kexec_core: Starting new kernel Welcome to Buildroot buildroot login: ===== Even when "quiet" kernel parameter is specified, "kexec_core: Starting new kernel" is printed. This message has KERN_EMERG level, but there is no emergency, it is a normal kexec operation, so quiet it down to appropriate KERN_NOTICE. Machines that have slow console baud rate benefit from less output. Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Simon Horman <horms@verge.net.au> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-09-25kexec: bail out upon SIGKILL when allocating memory.Tetsuo Handa
syzbot found that a thread can stall for minutes inside kexec_load() after that thread was killed by SIGKILL [1]. It turned out that the reproducer was trying to allocate 2408MB of memory using kimage_alloc_page() from kimage_load_normal_segment(). Let's check for SIGKILL before doing memory allocation. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Link: http://lkml.kernel.org/r/993c9185-d324-2640-d061-bed2dd18b1f7@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@syzkaller.appspotmail.com> Cc: Eric Biederman <ebiederm@xmission.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230Thomas Gleixner
Based on 2 normalized pattern(s): this source code is licensed under the gnu general public license version 2 see the file copying for more details this source code is licensed under general public license version 2 see extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 52 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-03power/suspend: Add function to disable secondaries for suspendNicholas Piggin
This adds a function to disable secondary CPUs for suspend that are not necessarily non-zero / non-boot CPUs. Platforms will be able to use this to suspend using non-zero CPUs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lkml.kernel.org/r/20190411033448.20842-3-npiggin@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-28mm: convert totalram_pages and totalhigh_pages variables to atomicArun KS
totalram_pages and totalhigh_pages are made static inline function. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes better to remove the lock and convert variables to atomic, with preventing poteintial store-to-read tearing as a bonus. [akpm@linux-foundation.org: coding style fixes] Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Suggested-by: Michal Hocko <mhocko@suse.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28mm: reference totalram_pages and managed_pages once per functionArun KS
Patch series "mm: convert totalram_pages, totalhigh_pages and managed pages to atomic", v5. This series converts totalram_pages, totalhigh_pages and zone->managed_pages to atomic variables. totalram_pages, zone->managed_pages and totalhigh_pages updates are protected by managed_page_count_lock, but readers never care about it. Convert these variables to atomic to avoid readers potentially seeing a store tear. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better to remove the lock and convert variables to atomic. With the change, preventing poteintial store-to-read tearing comes as a bonus. This patch (of 4): This is in preparation to a later patch which converts totalram_pages and zone->managed_pages to atomic variables. Please note that re-reading the value might lead to a different value and as such it could lead to unexpected behavior. There are no known bugs as a result of the current code but it is better to prevent from them in principle. Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-06kexec: Allocate decrypted control pages for kdump if SME is enabledLianbo Jiang
When SME is enabled in the first kernel, it needs to allocate decrypted pages for kdump because when the kdump kernel boots, these pages need to be accessed decrypted in the initial boot stage, before SME is enabled. [ bp: clean up text. ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: kexec@lists.infradead.org Cc: tglx@linutronix.de Cc: mingo@redhat.com Cc: hpa@zytor.com Cc: akpm@linux-foundation.org Cc: dan.j.williams@intel.com Cc: bhelgaas@google.com Cc: baiyaowei@cmss.chinamobile.com Cc: tiwai@suse.de Cc: brijesh.singh@amd.com Cc: dyoung@redhat.com Cc: bhe@redhat.com Cc: jroedel@suse.de Link: https://lkml.kernel.org/r/20180930031033.22110-3-lijiang@redhat.com
2018-06-15kexec: yield to scheduler when loading kimage segmentsJarrett Farnitano
Without yielding while loading kimage segments, a large initrd will block all other work on the CPU performing the load until it is completed. For example loading an initrd of 200MB on a low power single core system will lock up the system for a few seconds. To increase system responsiveness to other tasks at that time, call cond_resched() in both the crash kernel and normal kernel segment loading loops. I did run into a practical problem. Hardware watchdogs on embedded systems can have short timers on the order of seconds. If the system is locked up for a few seconds with only a single core available, the watchdog may not be pet in a timely fashion. If this happens, the hardware watchdog will fire and reset the system. This really only becomes a problem when you are working with a single core, a decently sized initrd, and have a constrained hardware watchdog. Link: http://lkml.kernel.org/r/1528738546-3328-1-git-send-email-jmf@amazon.com Signed-off-by: Jarrett Farnitano <jmf@amazon.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-18x86/mm, kexec: Allow kexec to be used with SMETom Lendacky
Provide support so that kexec can be used to boot a kernel when SME is enabled. Support is needed to allocate pages for kexec without encryption. This is needed in order to be able to reboot in the kernel in the same manner as originally booted. Additionally, when shutting down all of the CPUs we need to be sure to flush the caches and then halt. This is needed when booting from a state where SME was not active into a state where SME is active (or vice-versa). Without these steps, it is possible for cache lines to exist for the same physical location but tagged both with and without the encryption bit. This can cause random memory corruption when caches are flushed depending on which cacheline is written last. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: <kexec@lists.infradead.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Toshimitsu Kani <toshi.kani@hpe.com> Cc: kasan-dev@googlegroups.com Cc: kvm@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/b95ff075db3e7cd545313f2fb609a49619a09625.1500319216.git.thomas.lendacky@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-12kdump: protect vmcoreinfo data under the crash memoryXunlei Pang
Currently vmcoreinfo data is updated at boot time subsys_initcall(), it has the risk of being modified by some wrong code during system is running. As a result, vmcore dumped may contain the wrong vmcoreinfo. Later on, when using "crash", "makedumpfile", etc utility to parse this vmcore, we probably will get "Segmentation fault" or other unexpected errors. E.g. 1) wrong code overwrites vmcoreinfo_data; 2) further crashes the system; 3) trigger kdump, then we obviously will fail to recognize the crash context correctly due to the corrupted vmcoreinfo. Now except for vmcoreinfo, all the crash data is well protected(including the cpu note which is fully updated in the crash path, thus its correctness is guaranteed). Given that vmcoreinfo data is a large chunk prepared for kdump, we better protect it as well. To solve this, we relocate and copy vmcoreinfo_data to the crash memory when kdump is loading via kexec syscalls. Because the whole crash memory will be protected by existing arch_kexec_protect_crashkres() mechanism, we naturally protect vmcoreinfo_data from write(even read) access under kernel direct mapping after kdump is loaded. Since kdump is usually loaded at the very early stage after boot, we can trust the correctness of the vmcoreinfo data copied. On the other hand, we still need to operate the vmcoreinfo safe copy when crash happens to generate vmcoreinfo_note again, we rely on vmap() to map out a new kernel virtual address and update to use this new one instead in the following crash_save_vmcoreinfo(). BTW, we do not touch vmcoreinfo_note, because it will be fully updated using the protected vmcoreinfo_data after crash which is surely correct just like the cpu crash note. Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com Signed-off-by: Xunlei Pang <xlpang@redhat.com> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Young <dyoung@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Juergen Gross <jgross@suse.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-30objtool, x86: Add several functions and files to the objtool whitelistJosh Poimboeuf
In preparation for an objtool rewrite which will have broader checks, whitelist functions and files which cause problems because they do unusual things with the stack. These whitelists serve as a TODO list for which functions and files don't yet have undwarf unwinder coverage. Eventually most of the whitelists can be removed in favor of manual CFI hint annotations or objtool improvements. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/7f934a5d707a574bda33ea282e9478e627fb1829.1498659915.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-08ia64: reuse append_elf_note() and final_note() functionsHari Bathini
Get rid of multiple definitions of append_elf_note() & final_note() functions. Reuse these functions compiled under CONFIG_CRASH_CORE Also, define Elf_Word and use it instead of generic u32 or the more specific Elf64_Word. Link: http://lkml.kernel.org/r/149035342324.6881.11667840929850361402.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_COREHari Bathini
Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and reuse crashkernel parameter for fadump", v4. Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. This patchset removes dependency with CONFIG_KEXEC for crashkernel parameter and vmcoreinfo related code as it can be reused without kexec support. Also, crashkernel parameter is reused instead of fadump_reserve_mem to reserve memory for fadump. The first patch moves crashkernel parameter parsing and vmcoreinfo related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE. The second patch reuses the definitions of append_elf_note() & final_note() functions under CONFIG_CRASH_CORE in IA64 arch code. The third patch removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump) in powerpc. The next patch reuses crashkernel parameter for reserving memory for fadump, instead of the fadump_reserve_mem parameter. This has the advantage of using all syntaxes crashkernel parameter supports, for fadump as well. The last patch updates fadump kernel documentation about use of crashkernel parameter. This patch (of 5): Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. But currently, code related to vmcoreinfo and parsing of crashkernel parameter is built under CONFIG_KEXEC_CORE. This patch introduces CONFIG_CRASH_CORE and moves the above mentioned code under this config, allowing code reuse without dependency on CONFIG_KEXEC. There is no functional change with this patch. Link: http://lkml.kernel.org/r/149035338104.6881.4550894432615189948.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk updates from Petr Mladek: - Add Petr Mladek, Sergey Senozhatsky as printk maintainers, and Steven Rostedt as the printk reviewer. This idea came up after the discussion about printk issues at Kernel Summit. It was formulated and discussed at lkml[1]. - Extend a lock-less NMI per-cpu buffers idea to handle recursive printk() calls by Sergey Senozhatsky[2]. It is the first step in sanitizing printk as discussed at Kernel Summit. The change allows to see messages that would normally get ignored or would cause a deadlock. Also it allows to enable lockdep in printk(). This already paid off. The testing in linux-next helped to discover two old problems that were hidden before[3][4]. - Remove unused parameter by Sergey Senozhatsky. Clean up after a past change. [1] http://lkml.kernel.org/r/1481798878-31898-1-git-send-email-pmladek@suse.com [2] http://lkml.kernel.org/r/20161227141611.940-1-sergey.senozhatsky@gmail.com [3] http://lkml.kernel.org/r/20170215044332.30449-1-sergey.senozhatsky@gmail.com [4] http://lkml.kernel.org/r/20170217015932.11898-1-sergey.senozhatsky@gmail.com * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: printk: drop call_console_drivers() unused param printk: convert the rest to printk-safe printk: remove zap_locks() function printk: use printk_safe buffers in printk printk: report lost messages in printk safe/nmi contexts printk: always use deferred printk when flush printk_safe lines printk: introduce per-cpu safe_print seq buffer printk: rename nmi.c and exported api printk: use vprintk_func in vprintk() MAINTAINERS: Add printk maintainers
2017-02-08printk: rename nmi.c and exported apiSergey Senozhatsky
A preparation patch for printk_safe work. No functional change. - rename nmi.c to print_safe.c - add `printk_safe' prefix to some (which used both by printk-safe and printk-nmi) of the exported functions. Link: http://lkml.kernel.org/r/20161227141611.940-3-sergey.senozhatsky@gmail.com Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jan Kara <jack@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Calvin Owens <calvinowens@fb.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-01-11kexec: Switch to __pa_symbolLaura Abbott
__pa_symbol is the correct api to get the physical address of kernel symbols. Switch to it to allow for better debug checking. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-12-14kexec: add cond_resched into kimage_alloc_crash_control_pageszhong jiang
A soft lookup will occur when I run trinity in syscall kexec_load. the corresponding stack information is as follows. BUG: soft lockup - CPU#6 stuck for 22s! [trinity-c6:13859] Kernel panic - not syncing: softlockup: hung tasks CPU: 6 PID: 13859 Comm: trinity-c6 Tainted: G O L ----V------- 3.10.0-327.28.3.35.zhongjiang.x86_64 #1 Hardware name: Huawei Technologies Co., Ltd. Tecal BH622 V2/BC01SRSA0, BIOS RMIBV386 06/30/2014 Call Trace: <IRQ> dump_stack+0x19/0x1b panic+0xd8/0x214 watchdog_timer_fn+0x1cc/0x1e0 __hrtimer_run_queues+0xd2/0x260 hrtimer_interrupt+0xb0/0x1e0 ? call_softirq+0x1c/0x30 local_apic_timer_interrupt+0x37/0x60 smp_apic_timer_interrupt+0x3f/0x60 apic_timer_interrupt+0x6d/0x80 <EOI> ? kimage_alloc_control_pages+0x80/0x270 ? kmem_cache_alloc_trace+0x1ce/0x1f0 ? do_kimage_alloc_init+0x1f/0x90 kimage_alloc_init+0x12a/0x180 SyS_kexec_load+0x20a/0x260 system_call_fastpath+0x16/0x1b the first time allocation of control pages may take too much time because crash_res.end can be set to a higher value. we need to add cond_resched to avoid the issue. The patch have been tested and above issue is not appear. Link: http://lkml.kernel.org/r/1481164674-42775-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Xunlei Pang <xpang@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14kexec: export the value of phys_base instead of symbol addressBaoquan He
Currently in x86_64, the symbol address of phys_base is exported to vmcoreinfo. Dave Anderson complained this is really useless for his Crash implementation. Because in user-space utility Crash and Makedumpfile which exported vmcore information is mainly used for, value of phys_base is needed to covert virtual address of exported kernel symbol to physical address. Especially init_level4_pgt, if we want to access and go over the page table to look up a PA corresponding to VA, firstly we need calculate page_dir = SYMBOL(init_level4_pgt) - __START_KERNEL_map + phys_base; Now in Crash and Makedumpfile, we have to analyze the vmcore elf program header to get value of phys_base. As Dave said, it would be preferable if it were readily availabl in vmcoreinfo rather than depending upon the PT_LOAD semantics. Hence in this patch change to export the value of phys_base instead of its virtual address. And people also complained that KERNEL_IMAGE_SIZE exporting is x86_64 only, should be moved into arch dependent function arch_crash_save_vmcoreinfo. Do the moving in this patch. Link: http://lkml.kernel.org/r/1478568596-30060-2-git-send-email-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Thomas Garnier <thgarnie@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Xunlei Pang <xlpang@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Kees Cook <keescook@chromium.org> Cc: Eugene Surovegin <surovegin@google.com> Cc: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com> Cc: Dave Anderson <anderson@redhat.com> Cc: Pratyush Anand <panand@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02kexec: add restriction on kexec_load() segment sizeszhong jiang
I hit the following issue when run trinity in my system. The kernel is 3.4 version, but mainline has the same issue. The root cause is that the segment size is too large so the kerenl spends too long trying to allocate a page. Other cases will block until the test case quits. Also, OOM conditions will occur. Call Trace: __alloc_pages_nodemask+0x14c/0x8f0 alloc_pages_current+0xaf/0x120 kimage_alloc_pages+0x10/0x60 kimage_alloc_control_pages+0x5d/0x270 machine_kexec_prepare+0xe5/0x6c0 ? kimage_free_page_list+0x52/0x70 sys_kexec_load+0x141/0x600 ? vfs_write+0x100/0x180 system_call_fastpath+0x16/0x1b The patch changes sanity_check_segment_list() to verify that the usage by all segments does not exceed half of memory. [akpm@linux-foundation.org: fix for kexec-return-error-number-directly.patch, update comment] Link: http://lkml.kernel.org/r/1469625474-53904-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Suggested-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02kexec: add a kexec_crash_loaded() functionPetr Tesarik
Provide a wrapper function to be used by kernel code to check whether a crash kernel is loaded. It returns the same value that can be seen in /sys/kernel/kexec_crash_loaded by userspace programs. I'm exporting the function, because it will be used by Xen, and it is possible to compile Xen modules separately to enable the use of PV drivers with unmodified bare-metal kernels. Link: http://lkml.kernel.org/r/20160713121955.14969.69080.stgit@hananiah.suse.cz Signed-off-by: Petr Tesarik <ptesarik@suse.com> Cc: Juergen Gross <jgross@suse.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02kexec: allow architectures to override boot mappingRussell King
kexec physical addresses are the boot-time view of the system. For certain ARM systems (such as Keystone 2), the boot view of the system does not match the kernel's view of the system: the boot view uses a special alias in the lower 4GB of the physical address space. To cater for these kinds of setups, we need to translate between the boot view physical addresses and the normal kernel view physical addresses. This patch extracts the current transation points into linux/kexec.h, and allows an architecture to override the functions. Due to the translations required, we unfortunately end up with six translation functions, which are reduced down to four that the architecture can override. [akpm@linux-foundation.org: kexec.h needs asm/io.h for phys_to_virt()] Link: http://lkml.kernel.org/r/E1b8koP-0004HZ-Vf@rmk-PC.armlinux.org.uk Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Keerthy <j-keerthy@ti.com> Cc: Pratyush Anand <panand@redhat.com> Cc: Vitaly Andrianov <vitalya@ti.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02kdump: arrange for paddr_vmcoreinfo_note() to return phys_addr_tRussell King
On PAE systems (eg, ARM LPAE) the vmcore note may be located above 4GB physical on 32-bit architectures, so we need a wider type than "unsigned long" here. Arrange for paddr_vmcoreinfo_note() to return a phys_addr_t, thereby allowing it to be located above 4GB. This makes no difference for kexec-tools, as they already assume a 64-bit type when reading from this file. Link: http://lkml.kernel.org/r/E1b8koK-0004HS-K9@rmk-PC.armlinux.org.uk Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Reviewed-by: Pratyush Anand <panand@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Keerthy <j-keerthy@ti.com> Cc: Vitaly Andrianov <vitalya@ti.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02kexec: ensure user memory sizes do not wrapRussell King
Ensure that user memory sizes do not wrap around when validating the user input, which can lead to the following input validation working incorrectly. [akpm@linux-foundation.org: fix it for kexec-return-error-number-directly.patch] Link: http://lkml.kernel.org/r/E1b8koF-0004HM-5x@rmk-PC.armlinux.org.uk Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Reviewed-by: Pratyush Anand <panand@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Keerthy <j-keerthy@ti.com> Cc: Vitaly Andrianov <vitalya@ti.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02kexec: return error number directlyMinfei Huang
This is a cleanup patch to make kexec more clear to return error number directly. The variable result is useless, because there is no other function's return value assignes to it. So remove it. Link: http://lkml.kernel.org/r/1464179273-57668-1-git-send-email-mnghuan@gmail.com Signed-off-by: Minfei Huang <mnghuan@gmail.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Xunlei Pang <xlpang@redhat.com> Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23s390/kexec: consolidate crash_map/unmap_reserved_pages() and ↵Xunlei Pang
arch_kexec_protect(unprotect)_crashkres() Commit 3f625002581b ("kexec: introduce a protection mechanism for the crashkernel reserved memory") is a similar mechanism for protecting the crash kernel reserved memory to previous crash_map/unmap_reserved_pages() implementation, the new one is more generic in name and cleaner in code (besides, some arch may not be allowed to unmap the pgtable). Therefore, this patch consolidates them, and uses the new arch_kexec_protect(unprotect)_crashkres() to replace former crash_map/unmap_reserved_pages() which by now has been only used by S390. The consolidation work needs the crash memory to be mapped initially, this is done in machine_kdump_pm_init() which is after reserve_crashkernel(). Once kdump kernel is loaded, the new arch_kexec_protect_crashkres() implemented for S390 will actually unmap the pgtable like before. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Minfei Huang <mhuang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23kexec: introduce a protection mechanism for the crashkernel reserved memoryXunlei Pang
For the cases that some kernel (module) path stamps the crash reserved memory(already mapped by the kernel) where has been loaded the second kernel data, the kdump kernel will probably fail to boot when panic happens (or even not happens) leaving the culprit at large, this is unacceptable. The patch introduces a mechanism for detecting such cases: 1) After each crash kexec loading, it simply marks the reserved memory regions readonly since we no longer access it after that. When someone stamps the region, the first kernel will panic and trigger the kdump. The weak arch_kexec_protect_crashkres() is introduced to do the actual protection. 2) To allow multiple loading, once 1) was done we also need to remark the reserved memory to readwrite each time a system call related to kdump is made. The weak arch_kexec_unprotect_crashkres() is introduced to do the actual protection. The architecture can make its specific implementation by overriding arch_kexec_protect_crashkres() and arch_kexec_unprotect_crashkres(). Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Minfei Huang <mhuang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20printk/nmi: flush NMI messages on the system panicPetr Mladek
In NMI context, printk() messages are stored into per-CPU buffers to avoid a possible deadlock. They are normally flushed to the main ring buffer via an IRQ work. But the work is never called when the system calls panic() in the very same NMI handler. This patch tries to flush NMI buffers before the crash dump is generated. In this case it does not risk a double release and bails out when the logbuf_lock is already taken. The aim is to get the messages into the main ring buffer when possible. It makes them better accessible in the vmcore. Then the patch tries to flush the buffers second time when other CPUs are down. It might be more aggressive and reset logbuf_lock. The aim is to get the messages available for the consequent kmsg_dump() and console_flush_on_panic() calls. The patch causes vprintk_emit() to be called even in NMI context again. But it is done via printk_deferred() so that the console handling is skipped. Consoles use internal locks and we could not prevent a deadlock easily. They are explicitly called later when the crash dump is not generated, see console_flush_on_panic(). Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: David Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jiri Kosina <jkosina@suse.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-19mm: rename _count, field of the struct page, to _refcountJoonsoo Kim
Many developers already know that field for reference count of the struct page is _count and atomic type. They would try to handle it directly and this could break the purpose of page reference count tracepoint. To prevent direct _count modification, this patch rename it to _refcount and add warning message on the code. After that, developer who need to handle reference count will find that field should not be accessed directly. [akpm@linux-foundation.org: fix comments, per Vlastimil] [akpm@linux-foundation.org: Documentation/vm/transhuge.txt too] [sfr@canb.auug.org.au: sync ethernet driver changes] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Sunil Goutham <sgoutham@cavium.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Manish Chopra <manish.chopra@qlogic.com> Cc: Yuval Mintz <yuval.mintz@qlogic.com> Cc: Tariq Toukan <tariqt@mellanox.com> Cc: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-28kexec: export OFFSET(page.compound_head) to find out compound tail pageAtsushi Kumagai
PageAnon() always look at head page to check PAGE_MAPPING_ANON and tail page's page->mapping has just a poisoned data since commit 1c290f642101 ("mm: sanitize page->mapping for tail pages"). If makedumpfile checks page->mapping of a compound tail page to distinguish anonymous page as usual, it must fail in newer kernel. So it's necessary to export OFFSET(page.compound_head) to avoid checking compound tail pages. The problem is that unnecessary hugepages won't be removed from a dump file in kernels 4.5.x and later. This means that extra disk space would be consumed. It's a problem, but not critical. Signed-off-by: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-28kexec: update VMCOREINFO for compound_order/dtorAtsushi Kumagai
makedumpfile refers page.lru.next to get the order of compound pages for page filtering. However, now the order is stored in page.compound_order, hence VMCOREINFO should be updated to export the offset of page.compound_order. The fact is, page.compound_order was introduced already in kernel 4.0, but the offset of it was the same as page.lru.next until kernel 4.3, so this was not actual problem. The above can be said also for page.lru.prev and page.compound_dtor, it's necessary to detect hugetlbfs pages. Further, the content was changed from direct address to the ID which means dtor. The problem is that unnecessary hugepages won't be removed from a dump file in kernels 4.4.x and later. This means that extra disk space would be consumed. It's a problem, but not critical. Signed-off-by: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-30kexec: Set IORESOURCE_SYSTEM_RAM for System RAMToshi Kani
Set proper ioresource flags and types for crash kernel reservation areas. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Minfei Huang <mnfhuang@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: kexec@lists.infradead.org Cc: linux-arch@vger.kernel.org Cc: linux-mm <linux-mm@kvack.org> Link: http://lkml.kernel.org/r/1453841853-11383-8-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-20kernel/kexec_core.c: use list_for_each_entry_safe in kimage_free_page_listGeliang Tang
Use list_for_each_entry_safe() instead of list_for_each_safe() to simplify the code. Signed-off-by: Geliang Tang <geliangtang@163.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>