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? thanks, greg k-h
