linux-kernel - [PATCH] mm: use blk_io_schedule() for avoiding task hung in sync io

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1596461807-21087-1-git-send-email-xianting_tian@126.com>
Date:   Mon,  3 Aug 2020 09:36:47 -0400
From:   Xianting Tian <xianting_tian@....com>
To:     akpm@...ux-foundation.org
Cc:     linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: [PATCH] mm: use blk_io_schedule() for avoiding task hung in sync io

swap_readpage() does the sync io for one page, the io is not big, normally,
the io can be finished quickly, but it may take long time or wait forever
in case of io failure or discard.
This patch is to use blk_io_schedule() instead of io_schedule() to avoid
task hung and crash(when set /proc/sys/kernel/hung_task_panic) in case of
above exception occur.
We have prevented task hung in submit_bio_wait(), blk_execute_rq() and
__blkdev_direct_IO().

Signed-off-by: Xianting Tian <xianting_tian@....com>
---
 mm/page_io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_io.c b/mm/page_io.c
index e8726f3..5d52f7b 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -424,7 +424,7 @@ int swap_readpage(struct page *page, bool synchronous)
 			break;

 		if (!blk_poll(disk->queue, qc, true))
-			io_schedule();
+			blk_io_schedule();
 	}
 	__set_current_state(TASK_RUNNING);
 	bio_put(bio);
-- 
1.8.3.1