On 6/22/23 07:40, Christoph Hellwig wrote:
On Thu, Jun 22, 2023 at 06:54:41AM -0700, Guenter Roeck wrote:
On 6/21/23 23:00, Christoph Hellwig wrote:
Hi Guenter,
can you try this patch?
diff --git a/block/early-lookup.c b/block/early-lookup.c
index a5be3c68ed079c..66e4514d671179 100644
--- a/block/early-lookup.c
+++ b/block/early-lookup.c
@@ -174,7 +174,7 @@ static int __init devt_from_devname(const char *name, dev_t *devt)
while (p > s && isdigit(p[-1]))
p--;
if (p == s || !*p || *p == '0')
- return -EINVAL;
+ return -ENODEV;
/* try disk name without <part number> */
part = simple_strtoul(p, NULL, 10);
Not completely. Tests with root=/dev/sda still fail.
"name" passed to devt_from_devname() is "sda".
for (p = s; *p; p++) {
if (*p == '/')
*p = '!';
}
advances 'p' to the end of the string.
while (p > s && isdigit(p[-1]))
p--;
moves it back to point to the first digit (if there is one).
if (p == s || !*p || *p == '0')
return -EINVAL;
then fails because *p is 0. In other words, the function only accepts
drive names with digits at the end (and the first digit must not be '0').
I don't recall how I hit the other condition earlier. I have various
"/dev/mmcblkX" in my tests, where X can be any number including 0.
Maybe those fail randomly as well.
Overall I am not sure though what an "invalid" devicename is supposed
to be in this context. I have "sda", "sr0", "vda", "mtdblkX",
"nvme0n1", "mmcblkX", and "hda". Why would any of those not be eligible
for "rootwait" ?
In practice, everything not ending with a digit, or ending with
'0', fails the first test. Everything ending with a digit > 0
fails the second test. But "humptydump3p4" passes all those tests.
Yeah. I guess I should give up on the idea of error out in this
particular parser. The idea sounded good, but I guess it doesn't
work. So we'll probably want his fix:
Yes, that fixes the problem for me.
Guenter
diff --git a/block/early-lookup.c b/block/early-lookup.c
index a5be3c68ed079c..9e2d5a19de1b3b 100644
--- a/block/early-lookup.c
+++ b/block/early-lookup.c
@@ -174,7 +174,7 @@ static int __init devt_from_devname(const char *name, dev_t *devt)
while (p > s && isdigit(p[-1]))
p--;
if (p == s || !*p || *p == '0')
- return -EINVAL;
+ return -ENODEV;
/* try disk name without <part number> */
part = simple_strtoul(p, NULL, 10);
@@ -185,7 +185,7 @@ static int __init devt_from_devname(const char *name, dev_t *devt)
/* try disk name without p<part number> */
if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
- return -EINVAL;
+ return -ENODEV;
p[-1] = '\0';
*devt = blk_lookup_devt(s, part);
if (*devt)
