624fa7790f
In the scsi_transport_srp implementation it cannot be avoided to
iterate over a klist from atomic context when using the legacy block
layer instead of blk-mq. Hence this patch that makes it safe to use
klists in atomic context. This patch avoids that lockdep reports the
following:
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&(&k->k_lock)->rlock);
local_irq_disable();
lock(&(&q->__queue_lock)->rlock);
lock(&(&k->k_lock)->rlock);
<Interrupt>
lock(&(&q->__queue_lock)->rlock);
stack backtrace:
Workqueue: kblockd blk_timeout_work
Call Trace:
dump_stack+0xa4/0xf5
check_usage+0x6e6/0x700
__lock_acquire+0x185d/0x1b50
lock_acquire+0xd2/0x260
_raw_spin_lock+0x32/0x50
klist_next+0x47/0x190
device_for_each_child+0x8e/0x100
srp_timed_out+0xaf/0x1d0 [scsi_transport_srp]
scsi_times_out+0xd4/0x410 [scsi_mod]
blk_rq_timed_out+0x36/0x70
blk_timeout_work+0x1b5/0x220
process_one_work+0x4fe/0xad0
worker_thread+0x63/0x5a0
kthread+0x1c1/0x1e0
ret_from_fork+0x24/0x30
See also commit
|
||
---|---|---|
arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: 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. See Documentation/00-INDEX for a list of what is contained in each file. 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.