With the following patch
diff --git a/block/early-lookup.c b/block/early-lookup.c
index 3effbd0d35e9..9e5b11270f8e 100644
--- a/block/early-lookup.c
+++ b/block/early-lookup.c
@@ -138,6 +138,7 @@ static dev_t __init blk_lookup_devt(const char
*name, int partno)
/* We need to return the right devno, even
* if the partition doesn't exist yet.
*/
+ pr_err("%s: %s:%d doesn't exist yet\n", __func__, name, partno);
devt = MKDEV(MAJOR(dev->devt),
MINOR(dev->devt) + partno);
} else {
@@ -165,8 +166,10 @@ static int __init devt_from_devname(const char
*name, dev_t *devt)
}
*devt = blk_lookup_devt(s, 0);
- if (*devt)
+ if (*devt) {
+ pr_err("%s: %s found\n", __func__, name);
return 0;
+ }
/*
* Try non-existent, but valid partition, which may only exist after
@@ -181,16 +184,20 @@ static int __init devt_from_devname(const char
*name, dev_t *devt)
part = simple_strtoul(p, NULL, 10);
*p = '\0';
*devt = blk_lookup_devt(s, part);
- if (*devt)
+ if (*devt) {
+ pr_err("%s: %s:%d found without #\n", __func__, name, part);
return 0;
+ }
/* try disk name without p<part number> */
if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
return -ENODEV;
p[-1] = '\0';
*devt = blk_lookup_devt(s, part);
- if (*devt)
+ if (*devt) {
+ pr_err("%s: %s:%d found without p#\n", __func__, name, part);
return 0;
+ }
return -ENODEV;
}
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 32d49100dff5..9110cce01bee 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -375,6 +375,7 @@ static int mmc_blk_open(struct gendisk *disk,
blk_mode_t mode)
}
mutex_unlock(&block_mutex);
+ pr_err("%s: ret=%d\n", __func__, ret);
return ret;
}
I end up with the following messages:
mmc_blk_open: ret=0
blk_lookup_devt: mmcblk0:2 doesn't exist yet
devt_from_devname: mmcblk0p2:2 found without p#
blk_lookup_devt: mmcblk0:2 doesn't exist yet
devt_from_devname: mmcblk0p2:2 found without p#
device-mapper: table: 254:0: verity: Data device lookup failed (-ENXIO)
device-mapper: ioctl: error adding target to table
It seems like mmc_blk_open is not to blame.
Sven
On 4/9/24 4:23 PM, Christoph Hellwig wrote:
On Tue, Apr 09, 2024 at 01:33:13PM +0200, Sven wrote:
Hi,
I'm using dm-init to set up a dm-verity rootfs, i.e. my kernel command line
includes:
root=/dev/dm-0
dm-mod.waitfor=/dev/mmcblk0p3
dm-mod.create="rootfs,,0,ro,0 614400 verity 1 /dev/mmcblk0p3 /dev/mmcblk0p3
1024 4096 307200 76801 sha256 HASH HASH"
Occasionally, my device refuses to boot with the following errors:
device-mapper: table: 254:0: verity: Data device lookup failed (-ENXIO)
device-mapper: ioctl: error adding target to table
There appears to be a race condition somewhere. This problem started to
appear when updating from kernel version 5.15.148 to 6.6.22. Looking at the
changes between the versions, this patch seems relevant:
https://lore.kernel.org/all/20230531125535.676098-19-hch@xxxxxx/
It appears that early_lookup_bdev in dm_init_init would succeed even if the
partition block device is not there yet but the parent block device is.
Could that explain why the subsequent device lookup for the partition
fails?
-ENXIO isn't really an error that should come from the early block
device lookup. On the other hand mmc_blk_open can return -ENXIO
and block device open return values end up here. Can you throw
a printk or trace probe of your choice into mmc_blk_open to see if
that's the culprit?
