9f3fe29d77
RCU protection was removed in the commit 2d32777d60de ("raid1: remove rcu
protection to access rdev from conf").
However, the code in fix_read_error does rcu_dereference outside
rcu_read_lock - this triggers the following warning. The warning is
triggered by a LVM2 test shell/integrity-caching.sh.
This commit removes rcu_dereference.
=============================
WARNING: suspicious RCU usage
6.7.0 #2 Not tainted
-----------------------------
drivers/md/raid1.c:2265 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
no locks held by mdX_raid1/1859.
stack backtrace:
CPU: 2 PID: 1859 Comm: mdX_raid1 Not tainted 6.7.0 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x60/0x70
lockdep_rcu_suspicious+0x153/0x1b0
raid1d+0x1732/0x1750 [raid1]
? lock_acquire+0x9f/0x270
? finish_wait+0x3d/0x80
? md_thread+0xf7/0x130 [md_mod]
? lock_release+0xaa/0x230
? md_register_thread+0xd0/0xd0 [md_mod]
md_thread+0xa0/0x130 [md_mod]
? housekeeping_test_cpu+0x30/0x30
kthread+0xdc/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x28/0x40
? kthread_complete_and_exit+0x20/0x20
ret_from_fork_asm+0x11/0x20
</TASK>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: ca294b34aaf3 ("md/raid1: support read error check")
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/51539879-e1ca-fde3-b8b4-8934ddedcbc@redhat.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.