From: Qilin Tan qilin.tan@mediatek.com
commit 144f1cd40bf91fb3ac1d41806470756ce774f389 upstream.
Made iostat lock irq safe to avoid potentinal deadlock.
Deadlock scenario: f2fs_attr_store -> f2fs_sbi_store -> _sbi_store -> spin_lock(sbi->iostat_lock) <interrupt request> -> scsi_end_request -> bio_endio -> f2fs_dio_read_end_io -> f2fs_update_iostat -> spin_lock_irqsave(sbi->iostat_lock) ===> Dead lock here
Fixes: 61803e984307 ("f2fs: fix iostat related lock protection") Fixes: a1e09b03e6f5 ("f2fs: use iomap for direct I/O") Signed-off-by: Qilin Tan qilin.tan@mediatek.com Reviewed-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Cc: Daniel Rosenberg drosen@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/f2fs/sysfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/fs/f2fs/sysfs.c +++ b/fs/f2fs/sysfs.c @@ -491,9 +491,9 @@ out: if (!strcmp(a->attr.name, "iostat_period_ms")) { if (t < MIN_IOSTAT_PERIOD_MS || t > MAX_IOSTAT_PERIOD_MS) return -EINVAL; - spin_lock(&sbi->iostat_lock); + spin_lock_irq(&sbi->iostat_lock); sbi->iostat_period_ms = (unsigned int)t; - spin_unlock(&sbi->iostat_lock); + spin_unlock_irq(&sbi->iostat_lock); return count; } #endif