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>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <7ba1f088-2dbb-74db-d9a2-1a7c466f9aa0@huaweicloud.com>
Date: Fri, 30 May 2025 14:43:26 +0800
From: Yu Kuai <yukuai1@...weicloud.com>
To: Yu Kuai <yukuai1@...weicloud.com>, mpatocka@...hat.com,
 zdenek.kabelac@...il.com, song@...nel.org
Cc: linux-raid@...r.kernel.org, linux-kernel@...r.kernel.org,
 yi.zhang@...wei.com, yangerkun@...wei.com, johnny.chenyi@...wei.com,
 "yukuai (C)" <yukuai3@...wei.com>
Subject: Re: [PATCH v2] md/raid1,raid10: don't handle IO error for REQ_RAHEAD
 and REQ_NOWAIT

在 2025/05/27 16:14, Yu Kuai 写道:
> From: Yu Kuai <yukuai3@...wei.com>
> 
> IO with REQ_RAHEAD or REQ_NOWAIT can fail early, even if the storage medium
> is fine, hence record badblocks or remove the disk from array does not
> make sense.
> 
> This problem if found by lvm2 test lvcreate-large-raid, where dm-zero
> will fail read ahead IO directly.
> 
> Reported-and-tested-by: Mikulas Patocka <mpatocka@...hat.com>
> Closes: https://lore.kernel.org/all/34fa755d-62c8-4588-8ee1-33cb1249bdf2@redhat.com/
> Signed-off-by: Yu Kuai <yukuai3@...wei.com>
> ---
> Changes in v2:
>   - handle REQ_NOWAIT as well.
> 
>   drivers/md/raid1-10.c | 10 ++++++++++
>   drivers/md/raid1.c    | 19 ++++++++++---------
>   drivers/md/raid10.c   | 11 ++++++-----
>   3 files changed, 26 insertions(+), 14 deletions(-)
> 

Applied to md-6.16
Thanks

> diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c
> index c7efd8aab675..b8b3a9069701 100644
> --- a/drivers/md/raid1-10.c
> +++ b/drivers/md/raid1-10.c
> @@ -293,3 +293,13 @@ static inline bool raid1_should_read_first(struct mddev *mddev,
>   
>   	return false;
>   }
> +
> +/*
> + * bio with REQ_RAHEAD or REQ_NOWAIT can fail at anytime, before such IO is
> + * submitted to the underlying disks, hence don't record badblocks or retry
> + * in this case.
> + */
> +static inline bool raid1_should_handle_error(struct bio *bio)
> +{
> +	return !(bio->bi_opf & (REQ_RAHEAD | REQ_NOWAIT));
> +}
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index 657d481525be..19c5a0ce5a40 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -373,14 +373,16 @@ static void raid1_end_read_request(struct bio *bio)
>   	 */
>   	update_head_pos(r1_bio->read_disk, r1_bio);
>   
> -	if (uptodate)
> +	if (uptodate) {
>   		set_bit(R1BIO_Uptodate, &r1_bio->state);
> -	else if (test_bit(FailFast, &rdev->flags) &&
> -		 test_bit(R1BIO_FailFast, &r1_bio->state))
> +	} else if (test_bit(FailFast, &rdev->flags) &&
> +		 test_bit(R1BIO_FailFast, &r1_bio->state)) {
>   		/* This was a fail-fast read so we definitely
>   		 * want to retry */
>   		;
> -	else {
> +	} else if (!raid1_should_handle_error(bio)) {
> +		uptodate = 1;
> +	} else {
>   		/* If all other devices have failed, we want to return
>   		 * the error upwards rather than fail the last device.
>   		 * Here we redefine "uptodate" to mean "Don't want to retry"
> @@ -451,16 +453,15 @@ static void raid1_end_write_request(struct bio *bio)
>   	struct bio *to_put = NULL;
>   	int mirror = find_bio_disk(r1_bio, bio);
>   	struct md_rdev *rdev = conf->mirrors[mirror].rdev;
> -	bool discard_error;
>   	sector_t lo = r1_bio->sector;
>   	sector_t hi = r1_bio->sector + r1_bio->sectors;
> -
> -	discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
> +	bool ignore_error = !raid1_should_handle_error(bio) ||
> +		(bio->bi_status && bio_op(bio) == REQ_OP_DISCARD);
>   
>   	/*
>   	 * 'one mirror IO has finished' event handler:
>   	 */
> -	if (bio->bi_status && !discard_error) {
> +	if (bio->bi_status && !ignore_error) {
>   		set_bit(WriteErrorSeen,	&rdev->flags);
>   		if (!test_and_set_bit(WantReplacement, &rdev->flags))
>   			set_bit(MD_RECOVERY_NEEDED, &
> @@ -511,7 +512,7 @@ static void raid1_end_write_request(struct bio *bio)
>   
>   		/* Maybe we can clear some bad blocks. */
>   		if (rdev_has_badblock(rdev, r1_bio->sector, r1_bio->sectors) &&
> -		    !discard_error) {
> +		    !ignore_error) {
>   			r1_bio->bios[mirror] = IO_MADE_GOOD;
>   			set_bit(R1BIO_MadeGood, &r1_bio->state);
>   		}
> diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
> index dce06bf65016..b74780af4c22 100644
> --- a/drivers/md/raid10.c
> +++ b/drivers/md/raid10.c
> @@ -399,6 +399,8 @@ static void raid10_end_read_request(struct bio *bio)
>   		 * wait for the 'master' bio.
>   		 */
>   		set_bit(R10BIO_Uptodate, &r10_bio->state);
> +	} else if (!raid1_should_handle_error(bio)) {
> +		uptodate = 1;
>   	} else {
>   		/* If all other devices that store this block have
>   		 * failed, we want to return the error upwards rather
> @@ -456,9 +458,8 @@ static void raid10_end_write_request(struct bio *bio)
>   	int slot, repl;
>   	struct md_rdev *rdev = NULL;
>   	struct bio *to_put = NULL;
> -	bool discard_error;
> -
> -	discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
> +	bool ignore_error = !raid1_should_handle_error(bio) ||
> +		(bio->bi_status && bio_op(bio) == REQ_OP_DISCARD);
>   
>   	dev = find_bio_disk(conf, r10_bio, bio, &slot, &repl);
>   
> @@ -472,7 +473,7 @@ static void raid10_end_write_request(struct bio *bio)
>   	/*
>   	 * this branch is our 'one mirror IO has finished' event handler:
>   	 */
> -	if (bio->bi_status && !discard_error) {
> +	if (bio->bi_status && !ignore_error) {
>   		if (repl)
>   			/* Never record new bad blocks to replacement,
>   			 * just fail it.
> @@ -527,7 +528,7 @@ static void raid10_end_write_request(struct bio *bio)
>   		/* Maybe we can clear some bad blocks. */
>   		if (rdev_has_badblock(rdev, r10_bio->devs[slot].addr,
>   				      r10_bio->sectors) &&
> -		    !discard_error) {
> +		    !ignore_error) {
>   			bio_put(bio);
>   			if (repl)
>   				r10_bio->devs[slot].repl_bio = IO_MADE_GOOD;
> 


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ