From: Jens Axboe axboe@kernel.dk
mainline inclusion from mainline-v6.9-rc1 commit b874d4aae58b92144ec2c8fa5dc0a27c98388fcc category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IAGRKP
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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We should not have any callers of this from non-task context, but Jakub ran [1] into one from blk-iocost. Rather than risk running into others, or future ones, just limit blk_time_get_ns() to when it is called from a task. Any other usage is invalid.
[1] https://lore.kernel.org/lkml/CAHk-=wiOaBLqarS2uFhM1YdwOvCX4CZaWkeyNDY1zONpbY...
Fixes: da4c8c3d0975 ("block: cache current nsec time in struct blk_plug") Reported-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Yu Kuai yukuai3@huawei.com --- block/blk.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/blk.h b/block/blk.h index d02b515fc448..cbacf55d0b09 100644 --- a/block/blk.h +++ b/block/blk.h @@ -483,7 +483,7 @@ static inline u64 blk_time_get_ns(void) { struct blk_plug *plug = current->plug;
- if (!plug) + if (!plug || !in_task()) return ktime_get_ns();
/*