diff options
| author | Niklas Hambüchen <mail@nh2.me> | 2019-04-29 10:23:14 +0200 |
|---|---|---|
| committer | Simon Horman <horms@verge.net.au> | 2019-05-15 09:45:41 +0200 |
| commit | c072bd13abbe497d28e4235e2cf416f4aee65754 (patch) | |
| tree | aca6c77f82f5dca8ec2e9694b215b7d58470363a /kexec | |
| parent | 23aaa44614a02d2184951142125cb55b36cef40a (diff) | |
| download | kexec-tools-c072bd13abbe497d28e4235e2cf416f4aee65754.tar.gz | |
x86: Find mounts by FS type, not name
The name in mount invocations like
mount -t debugfs debugfs /sys/kernel/debug
is nothing but convention and cannot be relied upon.
For example, https://www.kernel.org/doc/Documentation/filesystems/debugfs.txt
recommends making the name "none" instead:
mount -t debugfs none /sys/kernel/debug
and many existing systems use mounts named "none" or otherwise.
Using `mnt_type` instead of `mnt_fsname` allows kexec to work
on such systems.
This fixes another instance of `poweroff` not working on kexec'ed
kernels because the lack of correctly matched mount results in EFI
variables not being read and propagated.
Signed-off-by: Niklas Hambüchen <mail@nh2.me>
Signed-off-by: Simon Horman <horms@verge.net.au>
Diffstat (limited to 'kexec')
| -rw-r--r-- | kexec/arch/i386/x86-linux-setup.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/kexec/arch/i386/x86-linux-setup.c b/kexec/arch/i386/x86-linux-setup.c index 74fb0c46..b643c8b7 100644 --- a/kexec/arch/i386/x86-linux-setup.c +++ b/kexec/arch/i386/x86-linux-setup.c @@ -433,8 +433,12 @@ out: * This really only makes sense for virtual filesystems that are only expected * to be mounted once (sysfs, debugsfs, proc), as it will return the first * instance listed in /proc/mounts, falling back to mtab if absent. + * We search by type and not by name because the name can be anything; + * while setting the name equal to the mount point is common, it cannot be + * relied upon, as even kernel documentation examples recommends using + * "none" as the name e.g. for debugfs. */ -char *find_mnt_by_fsname(char *fsname) +char *find_mnt_by_type(char *type) { FILE *mtab; struct mntent *mnt; @@ -448,7 +452,7 @@ char *find_mnt_by_fsname(char *fsname) if (!mtab) return NULL; for(mnt = getmntent(mtab); mnt; mnt = getmntent(mtab)) { - if (strcmp(mnt->mnt_fsname, fsname) == 0) + if (strcmp(mnt->mnt_type, type) == 0) break; } mntdir = mnt ? strdup(mnt->mnt_dir) : NULL; @@ -463,7 +467,7 @@ static int get_bootparam(void *buf, off_t offset, size_t size) char filename[PATH_MAX]; int err, has_sysfs_params = 0; - sysfs_mnt = find_mnt_by_fsname("sysfs"); + sysfs_mnt = find_mnt_by_type("sysfs"); if (sysfs_mnt) { snprintf(filename, PATH_MAX, "%s/%s", sysfs_mnt, "kernel/boot_params/data"); @@ -474,7 +478,7 @@ static int get_bootparam(void *buf, off_t offset, size_t size) } if (!has_sysfs_params) { - debugfs_mnt = find_mnt_by_fsname("debugfs"); + debugfs_mnt = find_mnt_by_type("debugfs"); if (!debugfs_mnt) return 1; snprintf(filename, PATH_MAX, "%s/%s", debugfs_mnt, |