Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
md: add check_new_feature module parameter
Raid checks if pad3 is zero when loading superblock from disk. Arrays
created with new features may fail to assemble on old kernels as pad3
is used.
Add module parameter check_new_feature to bypass this check.
Link: https://lore.kernel.org/linux-raid/20251103125757.1405796-5-linan666@huaweicloud.com
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
+9
-3
+9
-3
drivers/md/md.c
+9
-3
drivers/md/md.c
···
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339
*/
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static bool create_on_open = true;
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static bool legacy_async_del_gendisk = true;
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+
static bool check_new_feature = true;
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/*
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* We have a system wide 'event count' that is incremented
···
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}
1853
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if (sb->pad0 ||
1854
1853
sb->pad3[0] ||
1855
-
memcmp(sb->pad3, sb->pad3+1, sizeof(sb->pad3) - sizeof(sb->pad3[1])))
1856
-
/* Some padding is non-zero, might be a new feature */
1857
-
return -EINVAL;
1854
+
memcmp(sb->pad3, sb->pad3+1, sizeof(sb->pad3) - sizeof(sb->pad3[1]))) {
1855
+
pr_warn("Some padding is non-zero on %pg, might be a new feature\n",
1856
+
rdev->bdev);
1857
+
if (check_new_feature)
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+
return -EINVAL;
1859
+
pr_warn("check_new_feature is disabled, data corruption possible\n");
1860
+
}
1858
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rdev->preferred_minor = 0xffff;
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rdev->data_offset = le64_to_cpu(sb->data_offset);
···
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10741
module_param_call(new_array, add_named_array, NULL, NULL, S_IWUSR);
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module_param(create_on_open, bool, S_IRUSR|S_IWUSR);
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module_param(legacy_async_del_gendisk, bool, 0600);
10744
+
module_param(check_new_feature, bool, 0600);
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MODULE_LICENSE("GPL");
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MODULE_DESCRIPTION("MD RAID framework");