kernel/linux.git/lib/stackdepot.c, branch v5.16.12

lib, stackdepot: add helper to print stack entries into buffer

2021-11-09T18:02:50+00:00

To print stack entries into a buffer, users of stackdepot, first get a list of stack entries using stack_depot_fetch and then print this list into a buffer using stack_trace_snprint. Provide a helper in stackdepot for this purpose. Also change above mentioned users to use this helper. [imran.f.khan@oracle.com: fix build error] Link: https://lkml.kernel.org/r/20210915175321.3472770-4-imran.f.khan@oracle.com [imran.f.khan@oracle.com: export stack_depot_snprint() to modules] Link: https://lkml.kernel.org/r/20210916133535.3592491-4-imran.f.khan@oracle.com Link: https://lkml.kernel.org/r/20210915014806.3206938-4-imran.f.khan@oracle.com Signed-off-by: Imran Khan Suggested-by: Vlastimil Babka Acked-by: Vlastimil Babka Acked-by: Jani Nikula [i915] Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Daniel Vetter Cc: David Airlie Cc: Dmitry Vyukov Cc: Geert Uytterhoeven Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib, stackdepot: add helper to print stack entries

2021-11-09T18:02:50+00:00

To print a stack entries, users of stackdepot, first use stack_depot_fetch to get a list of stack entries and then use stack_trace_print to print this list. Provide a helper in stackdepot to print stack entries based on stackdepot handle. Also change above mentioned users to use this helper. Link: https://lkml.kernel.org/r/20210915014806.3206938-3-imran.f.khan@oracle.com Signed-off-by: Imran Khan Suggested-by: Vlastimil Babka Acked-by: Vlastimil Babka Reviewed-by: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Daniel Vetter Cc: David Airlie Cc: Dmitry Vyukov Cc: Geert Uytterhoeven Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib, stackdepot: check stackdepot handle before accessing slabs

2021-11-09T18:02:50+00:00

Patch series "lib, stackdepot: check stackdepot handle before accessing slabs", v2. PATCH-1: Checks validity of a stackdepot handle before proceeding to access stackdepot slab/objects. PATCH-2: Adds a helper in stackdepot, to allow users to print stack entries just by specifying the stackdepot handle. It also changes such users to use this new interface. PATCH-3: Adds a helper in stackdepot, to allow users to print stack entries into buffers just by specifying the stackdepot handle and destination buffer. It also changes such users to use this new interface. This patch (of 3): stack_depot_save allocates slabs that will be used for storing objects in future.If this slab allocation fails we may get to a situation where space allocation for a new stack_record fails, causing stack_depot_save to return 0 as handle. If user of this handle ends up invoking stack_depot_fetch with this handle value, current implementation of stack_depot_fetch will end up using slab from wrong index. To avoid this check handle value at the beginning. Link: https://lkml.kernel.org/r/20210915175321.3472770-1-imran.f.khan@oracle.com Link: https://lkml.kernel.org/r/20210915014806.3206938-1-imran.f.khan@oracle.com Link: https://lkml.kernel.org/r/20210915014806.3206938-2-imran.f.khan@oracle.com Signed-off-by: Imran Khan Suggested-by: Vlastimil Babka Acked-by: Vlastimil Babka Cc: Geert Uytterhoeven Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

stacktrace: move filter_irq_stacks() to kernel/stacktrace.c

2021-11-06T20:30:43+00:00

filter_irq_stacks() has little to do with the stackdepot implementation, except that it is usually used by users (such as KASAN) of stackdepot to reduce the stack trace. However, filter_irq_stacks() itself is not useful without a stack trace as obtained by stack_trace_save() and friends. Therefore, move filter_irq_stacks() to kernel/stacktrace.c, so that new users of filter_irq_stacks() do not have to start depending on STACKDEPOT only for filter_irq_stacks(). Link: https://lkml.kernel.org/r/20210923104803.2620285-1-elver@google.com Signed-off-by: Marco Elver Acked-by: Dmitry Vyukov Cc: Alexander Potapenko Cc: Jann Horn Cc: Aleksandr Nogikh Cc: Taras Madan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/stackdepot: introduce __stack_depot_save()

2021-11-06T20:30:33+00:00

Add __stack_depot_save(), which provides more fine-grained control over stackdepot's memory allocation behaviour, in case stackdepot runs out of "stack slabs". Normally stackdepot uses alloc_pages() in case it runs out of space; passing can_alloc==false to __stack_depot_save() prohibits this, at the cost of more likely failure to record a stack trace. Link: https://lkml.kernel.org/r/20210913112609.2651084-4-elver@google.com Signed-off-by: Marco Elver Tested-by: Shuah Khan Acked-by: Sebastian Andrzej Siewior Reviewed-by: Andrey Konovalov Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: "Gustavo A. R. Silva" Cc: Lai Jiangshan Cc: Taras Madan Cc: Tejun Heo Cc: Thomas Gleixner Cc: Vijayanand Jitta Cc: Vinayak Menon Cc: Walter Wu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/stackdepot: remove unused function argument

2021-11-06T20:30:33+00:00

alloc_flags in depot_alloc_stack() is no longer used; remove it. Link: https://lkml.kernel.org/r/20210913112609.2651084-3-elver@google.com Signed-off-by: Marco Elver Tested-by: Shuah Khan Acked-by: Sebastian Andrzej Siewior Reviewed-by: Andrey Konovalov Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: "Gustavo A. R. Silva" Cc: Lai Jiangshan Cc: Taras Madan Cc: Tejun Heo Cc: Thomas Gleixner Cc: Vijayanand Jitta Cc: Vinayak Menon Cc: Walter Wu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: fix spelling mistakes

2021-07-08T18:48:20+00:00

Fix some spelling mistakes in comments: permanentely ==> permanently wont ==> won't remaning ==> remaining succed ==> succeed shouldnt ==> shouldn't alpha-numeric ==> alphanumeric storeing ==> storing funtion ==> function documenation ==> documentation Determin ==> Determine intepreted ==> interpreted ammount ==> amount obious ==> obvious interupts ==> interrupts occured ==> occurred asssociated ==> associated taking into acount ==> taking into account squence ==> sequence stil ==> still contiguos ==> contiguous matchs ==> matches Link: https://lkml.kernel.org/r/20210607072555.12416-1-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei Reviewed-by: Jacob Keller Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: stackdepot: turn depot_lock spinlock to raw_spinlock

2021-05-07T02:24:12+00:00

In RT system, the spin_lock will be replaced by sleepable rt_mutex lock, in __call_rcu(), disable interrupts before calling kasan_record_aux_stack(), will trigger this calltrace: BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:951 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 19, name: pgdatinit0 Call Trace: ___might_sleep.cold+0x1b2/0x1f1 rt_spin_lock+0x3b/0xb0 stack_depot_save+0x1b9/0x440 kasan_save_stack+0x32/0x40 kasan_record_aux_stack+0xa5/0xb0 __call_rcu+0x117/0x880 __exit_signal+0xafb/0x1180 release_task+0x1d6/0x480 exit_notify+0x303/0x750 do_exit+0x678/0xcf0 kthread+0x364/0x4f0 ret_from_fork+0x22/0x30 Replace spinlock with raw_spinlock. Link: https://lkml.kernel.org/r/20210329084009.27013-1-qiang.zhang@windriver.com Signed-off-by: Zqiang Reported-by: Andrew Halaney Cc: Alexander Potapenko Cc: Gustavo A. R. Silva Cc: Vijayanand Jitta Cc: Vinayak Menon Cc: Yogesh Lal Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: stackdepot: fix ignoring return value warning

2021-02-26T17:41:04+00:00

Fix the below ignoring return value warning for kstrtobool in is_stack_depot_disabled function. lib/stackdepot.c: In function 'is_stack_depot_disabled': lib/stackdepot.c:154:2: warning: ignoring return value of 'kstrtobool' declared with attribute 'warn_unused_result' [-Wunused-result] Link: https://lkml.kernel.org/r/1612163048-28026-1-git-send-email-vjitta@codeaurora.org Fixes: b9779abb09a8 ("lib: stackdepot: add support to disable stack depot") Signed-off-by: Vijayanand Jitta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: stackdepot: add support to disable stack depot

2021-02-26T17:41:04+00:00

Add a kernel parameter stack_depot_disable to disable stack depot. So that stack hash table doesn't consume any memory when stack depot is disabled. The use case is CONFIG_PAGE_OWNER without page_owner=on. Without this patch, stackdepot will consume the memory for the hashtable. By default, it's 8M which is never trivial. With this option, in CONFIG_PAGE_OWNER configured system, page_owner=off, stack_depot_disable in kernel command line, we could save the wasted memory for the hashtable. [akpm@linux-foundation.org: fix CONFIG_STACKDEPOT=n build] Link: https://lkml.kernel.org/r/1611749198-24316-2-git-send-email-vjitta@codeaurora.org Signed-off-by: Vinayak Menon Signed-off-by: Vijayanand Jitta Cc: Alexander Potapenko Cc: Minchan Kim Cc: Yogesh Lal Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds