mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-05 10:31:46 +09:00
8c00db8017
[ Upstream commit 2f19c4b8395ccb6eb25ccafee883c8cfbe3fc193 ]
handle_receive_interrupt_napi_sp() running inside interrupt handler
could introduce inverse lock ordering between &dd->irq_src_lock
and &dd->uctxt_lock, if read_mod_write() is preempted by the isr.
[CPU0] | [CPU1]
hfi1_ipoib_dev_open() |
--> hfi1_netdev_enable_queues() |
--> enable_queues(rx) |
--> hfi1_rcvctrl() |
--> set_intr_bits() |
--> read_mod_write() |
--> spin_lock(&dd->irq_src_lock) |
| hfi1_poll()
| --> poll_next()
| --> spin_lock_irq(&dd->uctxt_lock)
|
| --> hfi1_rcvctrl()
| --> set_intr_bits()
| --> read_mod_write()
| --> spin_lock(&dd->irq_src_lock)
<interrupt> |
--> handle_receive_interrupt_napi_sp() |
--> set_all_fastpath() |
--> hfi1_rcd_get_by_index() |
--> spin_lock_irqsave(&dd->uctxt_lock) |
This flaw was found by an experimental static analysis tool I am
developing for irq-related deadlock.
To prevent the potential deadlock, the patch use spin_lock_irqsave()
on &dd->irq_src_lock inside read_mod_write() to prevent the possible
deadlock scenario.
Signed-off-by: Chengfeng Ye <dg573847474@gmail.com>
Link: https://lore.kernel.org/r/20230926101116.2797-1-dg573847474@gmail.com
Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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.