From: Baoquan He bhe@redhat.com
[ Upstream commit b1e213a9e31c20206f111ec664afcf31cbfe0dbb ]
On s390 systems (aka mainframes), it has classic channel devices for networking and permanent storage that are currently even more common than PCI devices. Hence it could have a fully functional s390 kernel with CONFIG_PCI=n, then the relevant iomem mapping functions [including ioremap(), devm_ioremap(), etc.] are not available.
Here let FSL_EDMA and INTEL_IDMA64 depend on HAS_IOMEM so that it won't be built to cause below compiling error if PCI is unset.
-------- ERROR: modpost: "devm_platform_ioremap_resource" [drivers/dma/fsl-edma.ko] undefined! ERROR: modpost: "devm_platform_ioremap_resource" [drivers/dma/idma64.ko] undefined! --------
Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202306211329.ticOJCSv-lkp@intel.com/ Signed-off-by: Baoquan He bhe@redhat.com Cc: Vinod Koul vkoul@kernel.org Cc: dmaengine@vger.kernel.org Link: https://lore.kernel.org/r/20230707135852.24292-2-bhe@redhat.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dma/Kconfig | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 1322461f1f3c5..66aad9dbd58c5 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -208,6 +208,7 @@ config FSL_DMA config FSL_EDMA tristate "Freescale eDMA engine support" depends on OF + depends on HAS_IOMEM select DMA_ENGINE select DMA_VIRTUAL_CHANNELS help @@ -268,6 +269,7 @@ config IMX_SDMA
config INTEL_IDMA64 tristate "Intel integrated DMA 64-bit support" + depends on HAS_IOMEM select DMA_ENGINE select DMA_VIRTUAL_CHANNELS help
From: Chengfeng Ye dg573847474@gmail.com
[ Upstream commit dd64f80587190265ca8a0f4be6c64c2fda6d3ac2 ]
As &qedi_percpu->p_work_lock is acquired by hard IRQ qedi_msix_handler(), other acquisitions of the same lock under process context should disable IRQ, otherwise deadlock could happen if the IRQ preempts the execution while the lock is held in process context on the same CPU.
qedi_cpu_offline() is one such function which acquires the lock in process context.
[Deadlock Scenario] qedi_cpu_offline() ->spin_lock(&p->p_work_lock) <irq> ->qedi_msix_handler() ->edi_process_completions() ->spin_lock_irqsave(&p->p_work_lock, flags); (deadlock here)
This flaw was found by an experimental static analysis tool I am developing for IRQ-related deadlocks.
The tentative patch fix the potential deadlock by spin_lock_irqsave() under process context.
Signed-off-by: Chengfeng Ye dg573847474@gmail.com Link: https://lore.kernel.org/r/20230726125655.4197-1-dg573847474@gmail.com Acked-by: Manish Rangankar mrangankar@marvell.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/qedi/qedi_main.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/qedi/qedi_main.c b/drivers/scsi/qedi/qedi_main.c index 92c4a367b7bd7..6b47921202eba 100644 --- a/drivers/scsi/qedi/qedi_main.c +++ b/drivers/scsi/qedi/qedi_main.c @@ -1910,8 +1910,9 @@ static int qedi_cpu_offline(unsigned int cpu) struct qedi_percpu_s *p = this_cpu_ptr(&qedi_percpu); struct qedi_work *work, *tmp; struct task_struct *thread; + unsigned long flags;
- spin_lock_bh(&p->p_work_lock); + spin_lock_irqsave(&p->p_work_lock, flags); thread = p->iothread; p->iothread = NULL;
@@ -1922,7 +1923,7 @@ static int qedi_cpu_offline(unsigned int cpu) kfree(work); }
- spin_unlock_bh(&p->p_work_lock); + spin_unlock_irqrestore(&p->p_work_lock, flags); if (thread) kthread_stop(thread); return 0;
linux-stable-mirror@lists.linaro.org
-
Sasha Levin