Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
After a successful SRP login response we call scsi_unblock_requests() to kick any pending IOs. The callback to process this SRP response happens in a tasklet and therefore is in softirq context. The result of such is that when blk-mq is enabled, it is no longer safe to call scsi_unblock_requests() from this context. The result of duing so triggers the following WARN_ON splat in dmesg after a host reset or CRQ reenablement. WARNING: CPU: 0 PID: 0 at block/blk-mq.c:1375 __blk_mq_run_hw_queue+0x120/0x180 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.0.0-rc8 #4 NIP [c0000000009771e0] __blk_mq_run_hw_queue+0x120/0x180 LR [c000000000977484] __blk_mq_delay_run_hw_queue+0x244/0x250 Call Trace: __blk_mq_delay_run_hw_queue+0x244/0x250 blk_mq_run_hw_queue+0x8c/0x1c0 blk_mq_run_hw_queues+0x60/0x90 scsi_run_queue+0x1e4/0x3b0 scsi_run_host_queues+0x48/0x80 login_rsp+0xb0/0x100 ibmvscsi_handle_crq+0x30c/0x3e0 ibmvscsi_task+0x54/0xe0 tasklet_action_common.isra.3+0xc4/0x1a0 __do_softirq+0x174/0x3f4 irq_exit+0xf0/0x120 __do_irq+0xb0/0x210 call_do_irq+0x14/0x24 do_IRQ+0x9c/0x130 hardware_interrupt_common+0x14c/0x150 This patch fixes the issue by introducing a new host action for unblocking the scsi requests in our seperate work thread. Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
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. 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.