From 23ac2a31c54f5bb39d6e11c47680e588b3a0ca81 Mon Sep 17 00:00:00 2001 From: Qiujun Huang Date: Sun, 4 Sep 2022 23:17:13 +0800 Subject: [PATCH] pstore/zone: Use GFP_ATOMIC to allocate zone buffer commit 99b3b837855b987563bcfb397cf9ddd88262814b upstream. There is a case found when triggering a panic_on_oom, pstore fails to dump kmsg. Because psz_kmsg_write_record can't get the new buffer. Handle this by using GFP_ATOMIC to allocate a buffer at lower watermark. Signed-off-by: Qiujun Huang Fixes: 335426c6dcdd ("pstore/zone: Provide way to skip "broken" zone for MTD devices") Cc: WeiXiong Liao Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/CAJRQjofRCF7wjrYmw3D7zd5QZnwHQq+F8U-mJDJ6NZ4bddYdLA@mail.gmail.com Signed-off-by: Greg Kroah-Hartman --- fs/pstore/zone.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c index 017d0d4..2770746 100644 --- a/fs/pstore/zone.c +++ b/fs/pstore/zone.c @@ -761,7 +761,7 @@ static inline int notrace psz_kmsg_write_record(struct psz_context *cxt, /* avoid destroying old data, allocate a new one */ len = zone->buffer_size + sizeof(*zone->buffer); zone->oldbuf = zone->buffer; - zone->buffer = kzalloc(len, GFP_KERNEL); + zone->buffer = kzalloc(len, GFP_ATOMIC); if (!zone->buffer) { zone->buffer = zone->oldbuf; return -ENOMEM; -- 2.7.4