From: js1304@gmail.com To: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>, Alexander Potapenko <glider@google.com>, Dmitry Vyukov <dvyukov@google.com>, kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Namhyung Kim <namhyung@kernel.org>, Wengang Wang <wen.gang.wang@oracle.com>, Joonsoo Kim <iamjoonsoo.kim@lge.com> Subject: [PATCH 10/18] vchecker: Use __GFP_ATOMIC to save stacktrace Date: Tue, 28 Nov 2017 16:48:45 +0900 [thread overview] Message-ID: <1511855333-3570-11-git-send-email-iamjoonsoo.kim@lge.com> (raw) In-Reply-To: <1511855333-3570-1-git-send-email-iamjoonsoo.kim@lge.com> From: Namhyung Kim <namhyung@kernel.org> Since we're finding a cause of broken data, it'd be desired not to miss any suspects. It doesn't use GFP_ATOMIC since it includes __GFP_HIGH which is for system making forward progress. It also adds a WARN_ON whenever it fails to allocate pages even with __GFP_ATOMIC. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> --- mm/kasan/vchecker.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/kasan/vchecker.c b/mm/kasan/vchecker.c index 6b3824f..df480d5 100644 --- a/mm/kasan/vchecker.c +++ b/mm/kasan/vchecker.c @@ -301,13 +301,20 @@ static noinline depot_stack_handle_t save_stack(int skip, bool *is_new) .max_entries = VCHECKER_STACK_DEPTH, .skip = skip, }; + depot_stack_handle_t handle; save_stack_trace(&trace); if (trace.nr_entries != 0 && trace.entries[trace.nr_entries-1] == ULONG_MAX) trace.nr_entries--; - return depot_save_stack(NULL, &trace, GFP_NOWAIT, is_new); + if (trace.nr_entries == 0) + return 0; + + handle = depot_save_stack(NULL, &trace, __GFP_ATOMIC, is_new); + WARN_ON(!handle); + + return handle; } static ssize_t vchecker_type_write(struct file *filp, const char __user *ubuf, -- 2.7.4
WARNING: multiple messages have this Message-ID (diff)
From: js1304@gmail.com To: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>, Alexander Potapenko <glider@google.com>, Dmitry Vyukov <dvyukov@google.com>, kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Namhyung Kim <namhyung@kernel.org>, Wengang Wang <wen.gang.wang@oracle.com>, Joonsoo Kim <iamjoonsoo.kim@lge.com> Subject: [PATCH 10/18] vchecker: Use __GFP_ATOMIC to save stacktrace Date: Tue, 28 Nov 2017 16:48:45 +0900 [thread overview] Message-ID: <1511855333-3570-11-git-send-email-iamjoonsoo.kim@lge.com> (raw) In-Reply-To: <1511855333-3570-1-git-send-email-iamjoonsoo.kim@lge.com> From: Namhyung Kim <namhyung@kernel.org> Since we're finding a cause of broken data, it'd be desired not to miss any suspects. It doesn't use GFP_ATOMIC since it includes __GFP_HIGH which is for system making forward progress. It also adds a WARN_ON whenever it fails to allocate pages even with __GFP_ATOMIC. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> --- mm/kasan/vchecker.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/kasan/vchecker.c b/mm/kasan/vchecker.c index 6b3824f..df480d5 100644 --- a/mm/kasan/vchecker.c +++ b/mm/kasan/vchecker.c @@ -301,13 +301,20 @@ static noinline depot_stack_handle_t save_stack(int skip, bool *is_new) .max_entries = VCHECKER_STACK_DEPTH, .skip = skip, }; + depot_stack_handle_t handle; save_stack_trace(&trace); if (trace.nr_entries != 0 && trace.entries[trace.nr_entries-1] == ULONG_MAX) trace.nr_entries--; - return depot_save_stack(NULL, &trace, GFP_NOWAIT, is_new); + if (trace.nr_entries == 0) + return 0; + + handle = depot_save_stack(NULL, &trace, __GFP_ATOMIC, is_new); + WARN_ON(!handle); + + return handle; } static ssize_t vchecker_type_write(struct file *filp, const char __user *ubuf, -- 2.7.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2017-11-28 7:49 UTC|newest] Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-11-28 7:48 [PATCH 00/18] introduce a new tool, valid access checker js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 01/18] mm/kasan: make some kasan functions global js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 02/18] vchecker: introduce the valid access checker js1304 2017-11-28 7:48 ` js1304 2017-11-28 19:41 ` Andi Kleen 2017-11-28 19:41 ` Andi Kleen 2017-11-29 5:36 ` Joonsoo Kim 2017-11-29 5:36 ` Joonsoo Kim 2017-12-01 5:08 ` kbuild test robot 2017-12-01 8:01 ` Joonsoo Kim 2017-12-01 8:01 ` Joonsoo Kim 2017-11-28 7:48 ` [PATCH 03/18] vchecker: mark/unmark the shadow of the allocated objects js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 04/18] vchecker: prepare per object memory for vchecker js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 05/18] vchecker: store/report callstack of value writer js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 06/18] lib/stackdepot: Add is_new arg to depot_save_stack js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 07/18] lib/stackdepot: extend stackdepot API to support per-user stackdepot js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 08/18] vchecker: Add 'callstack' checker js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 09/18] vchecker: Support toggle on/off of callstack check js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` js1304 [this message] 2017-11-28 7:48 ` [PATCH 10/18] vchecker: Use __GFP_ATOMIC to save stacktrace js1304 2017-11-28 7:48 ` [PATCH 11/18] vchecker: consistently exclude vchecker's stacktrace js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 12/18] vchecker: fix 'remove' handling on callstack checker js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 13/18] mm/vchecker: support inline KASAN build js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 14/18] mm/vchecker: make callstack depth configurable js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 15/18] mm/vchecker: pass allocation caller address to vchecker hook js1304 2017-11-28 7:48 ` js1304 2017-12-01 2:39 ` kbuild test robot 2017-12-01 3:01 ` kbuild test robot 2017-11-28 7:48 ` [PATCH 16/18] mm/vchecker: support allocation caller filter js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 17/18] lib/vchecker_test: introduce a sample for vchecker test js1304 2017-11-28 7:48 ` js1304 2017-11-28 7:48 ` [PATCH 18/18] doc: add vchecker document js1304 2017-11-28 7:48 ` js1304 2017-11-29 9:27 ` [PATCH 00/18] introduce a new tool, valid access checker Dmitry Vyukov 2017-11-29 9:27 ` Dmitry Vyukov 2017-12-01 7:46 ` Joonsoo Kim 2017-12-01 7:46 ` Joonsoo Kim 2017-12-22 1:51 ` Joonsoo Kim 2017-12-22 1:51 ` Joonsoo Kim 2018-01-18 22:39 ` Andrew Morton 2018-01-18 22:39 ` Andrew Morton
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