> On Mar 28, 2023, at 21:19, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > On Tue, Mar 28, 2023 at 09:02:27PM +0800, Muchun Song wrote: >> >> >> On 2023/3/28 20:01, gregkh@xxxxxxxxxxxxxxxxxxx wrote: >>> The patch below does not apply to the 5.15-stable tree. >>> If someone wants it applied there, or to any other stable or longterm >>> tree, then please email the backport, including the original git commit >>> id to <stable@xxxxxxxxxxxxxxx>. >>> >>> To reproduce the conflict and resubmit, you may use the following commands: >>> >>> git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y >>> git checkout FETCH_HEAD >>> git cherry-pick -x 1c86a188e03156223a34d09ce290b49bd4dd0403 >>> # <resolve conflicts, build, test, etc.> >>> git commit -s >>> git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '16800049118459@xxxxxxxxx' --subject-prefix 'PATCH 5.15.y' HEAD^.. >>> >>> Possible dependencies: >>> >>> 1c86a188e031 ("mm: kfence: fix using kfence_metadata without initialization in show_object()") >>> b33f778bba5e ("kfence: alloc kfence_pool after system startup") >>> 698361bca2d5 ("kfence: allow re-enabling KFENCE after system startup") >>> 07e8481d3c38 ("kfence: always use static branches to guard kfence_alloc()") >>> 08f6b10630f2 ("kfence: limit currently covered allocations when pool nearly full") >>> a9ab52bbcb52 ("kfence: move saving stack trace of allocations into __kfence_alloc()") >>> 9a19aeb56650 ("kfence: count unexpectedly skipped allocations") >>> >>> thanks, >>> >>> greg k-h >>> >>> ------------------ original commit in Linus's tree ------------------ >>> >>> From 1c86a188e03156223a34d09ce290b49bd4dd0403 Mon Sep 17 00:00:00 2001 >>> From: Muchun Song <muchun.song@xxxxxxxxx> >>> Date: Wed, 15 Mar 2023 11:44:41 +0800 >>> Subject: [PATCH] mm: kfence: fix using kfence_metadata without initialization >>> in show_object() >>> >>> The variable kfence_metadata is initialized in kfence_init_pool(), then, >>> it is not initialized if kfence is disabled after booting. In this case, >>> kfence_metadata will be used (e.g. ->lock and ->state fields) without >>> initialization when reading /sys/kernel/debug/kfence/objects. There will >>> be a warning if you enable CONFIG_DEBUG_SPINLOCK. Fix it by creating >>> debugfs files when necessary. >>> >>> Link: https://lkml.kernel.org/r/20230315034441.44321-1-songmuchun@xxxxxxxxxxxxx >>> Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure") >>> Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> >>> Tested-by: Marco Elver <elver@xxxxxxxxxx> >>> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> >>> Cc: Alexander Potapenko <glider@xxxxxxxxxx> >>> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> >>> Cc: Jann Horn <jannh@xxxxxxxxxx> >>> Cc: SeongJae Park <sjpark@xxxxxxxxx> >>> Cc: <stable@xxxxxxxxxxxxxxx> >>> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >>> >>> diff --git a/mm/kfence/core.c b/mm/kfence/core.c >>> index 5349c37a5dac..79c94ee55f97 100644 >>> --- a/mm/kfence/core.c >>> +++ b/mm/kfence/core.c >>> @@ -726,10 +726,14 @@ static const struct seq_operations objects_sops = { >>> }; >>> DEFINE_SEQ_ATTRIBUTE(objects); >>> -static int __init kfence_debugfs_init(void) >>> +static int kfence_debugfs_init(void) >>> { >>> - struct dentry *kfence_dir = debugfs_create_dir("kfence", NULL); >>> + struct dentry *kfence_dir; >>> + if (!READ_ONCE(kfence_enabled)) >>> + return 0; >>> + >>> + kfence_dir = debugfs_create_dir("kfence", NULL); >>> debugfs_create_file("stats", 0444, kfence_dir, NULL, &stats_fops); >>> debugfs_create_file("objects", 0400, kfence_dir, NULL, &objects_fops); >>> return 0; >>> @@ -883,6 +887,8 @@ static int kfence_init_late(void) >>> } >>> kfence_init_enable(); >>> + kfence_debugfs_init(); >>> + >>> return 0; >>> } >> >> I have implemented a following patch based on v5.15 branch. >> >> From ba26f344fa3e477456a3cc60488a7b8e5af0e88d Mon Sep 17 00:00:00 2001 >> From: Muchun Song <songmuchun@xxxxxxxxxxxxx> >> Date: Wed, 15 Mar 2023 11:44:41 +0800 >> Subject: [PATCH] mm: kfence: fix using kfence_metadata without >> initialization >> in show_object() >> >> The variable kfence_metadata is initialized in kfence_init_pool(), then, >> it is not initialized if kfence is disabled after booting. In this case, >> kfence_metadata will be used (e.g. ->lock and ->state fields) without >> initialization when reading /sys/kernel/debug/kfence/objects. There will >> be a warning if you enable CONFIG_DEBUG_SPINLOCK. Fix it by creating >> debugfs files when necessary. >> >> Link: >> https://lkml.kernel.org/r/20230315034441.44321-1-songmuchun@xxxxxxxxxxxxx >> Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure") >> Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> >> Tested-by: Marco Elver <elver@xxxxxxxxxx> >> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> >> Cc: Alexander Potapenko <glider@xxxxxxxxxx> >> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> >> Cc: Jann Horn <jannh@xxxxxxxxxx> >> Cc: SeongJae Park <sjpark@xxxxxxxxx> >> Cc: <stable@xxxxxxxxxxxxxxx> >> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >> --- >> mm/kfence/core.c | 8 ++++++-- >> 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/mm/kfence/core.c b/mm/kfence/core.c >> index 39a6c434e355..573f34e6af0b 100644 >> --- a/mm/kfence/core.c >> +++ b/mm/kfence/core.c >> @@ -678,10 +678,14 @@ static const struct file_operations objects_fops = { >> .release = seq_release, >> }; >> > > Patch is corrupted with the whitespace eaten by your email client. Can > you resend this in a format that it can be applied? I attach it here. Could you apply it? Thanks.
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> > thanks, > > greg k-h
