| Message ID | 20231212022158.358619-1-rex.zhang@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | dmaengine: idxd: Move dma_free_coherent() out of spinlocked context | expand |
On 12/11/2023 8:21 PM, Rex Zhang wrote: > Task may be rescheduled within dma_free_coherent(). So dma_free_coherent() > can't be called between spin_lock() and spin_unlock() to avoid Call Trace: > Call Trace: > <TASK> > dump_stack_lvl+0x37/0x50 > __might_resched+0x16a/0x1c0 > vunmap+0x2c/0x70 > __iommu_dma_free+0x96/0x100 > idxd_device_evl_free+0xd5/0x100 [idxd] > device_release_driver_internal+0x197/0x200 > unbind_store+0xa1/0xb0 > kernfs_fop_write_iter+0x120/0x1c0 > vfs_write+0x2d3/0x400 > ksys_write+0x63/0xe0 > do_syscall_64+0x44/0xa0 > entry_SYSCALL_64_after_hwframe+0x6e/0xd8 > Move it out of the context. > > Fixes: 244da66cda35 ("dmaengine: idxd: setup event log configuration") > Signed-off-by: Rex Zhang <rex.zhang@intel.com> > Reviewed-by: Dave Jiang <dave.jiang@intel.com> > Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> > --- Reviewed-by: Lijun Pan <lijun.pan@intel.com> > drivers/dma/idxd/device.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c > index 8f754f922217..fa0f880beae6 100644 > --- a/drivers/dma/idxd/device.c > +++ b/drivers/dma/idxd/device.c > @@ -802,6 +802,9 @@ static int idxd_device_evl_setup(struct idxd_device *idxd) > > static void idxd_device_evl_free(struct idxd_device *idxd) > { > + void *evl_log; > + unsigned int evl_log_size; > + dma_addr_t evl_dma; > union gencfg_reg gencfg; > union genctrl_reg genctrl; > struct device *dev = &idxd->pdev->dev; > @@ -822,11 +825,15 @@ static void idxd_device_evl_free(struct idxd_device *idxd) > iowrite64(0, idxd->reg_base + IDXD_EVLCFG_OFFSET); > iowrite64(0, idxd->reg_base + IDXD_EVLCFG_OFFSET + 8); > > - dma_free_coherent(dev, evl->log_size, evl->log, evl->dma); > bitmap_free(evl->bmap); > + evl_log = evl->log; > + evl_log_size = evl->log_size; > + evl_dma = evl->dma; > evl->log = NULL; > evl->size = IDXD_EVL_SIZE_MIN; > spin_unlock(&evl->lock); > + > + dma_free_coherent(dev, evl_log_size, evl_log, evl_dma); > } > > static void idxd_group_config_write(struct idxd_group *group)
diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c index 8f754f922217..fa0f880beae6 100644 --- a/drivers/dma/idxd/device.c +++ b/drivers/dma/idxd/device.c @@ -802,6 +802,9 @@ static int idxd_device_evl_setup(struct idxd_device *idxd) static void idxd_device_evl_free(struct idxd_device *idxd) { + void *evl_log; + unsigned int evl_log_size; + dma_addr_t evl_dma; union gencfg_reg gencfg; union genctrl_reg genctrl; struct device *dev = &idxd->pdev->dev; @@ -822,11 +825,15 @@ static void idxd_device_evl_free(struct idxd_device *idxd) iowrite64(0, idxd->reg_base + IDXD_EVLCFG_OFFSET); iowrite64(0, idxd->reg_base + IDXD_EVLCFG_OFFSET + 8); - dma_free_coherent(dev, evl->log_size, evl->log, evl->dma); bitmap_free(evl->bmap); + evl_log = evl->log; + evl_log_size = evl->log_size; + evl_dma = evl->dma; evl->log = NULL; evl->size = IDXD_EVL_SIZE_MIN; spin_unlock(&evl->lock); + + dma_free_coherent(dev, evl_log_size, evl_log, evl_dma); } static void idxd_group_config_write(struct idxd_group *group)
Task may be rescheduled within dma_free_coherent(). So dma_free_coherent() can't be called between spin_lock() and spin_unlock() to avoid Call Trace: Call Trace: <TASK> dump_stack_lvl+0x37/0x50 __might_resched+0x16a/0x1c0 vunmap+0x2c/0x70 __iommu_dma_free+0x96/0x100 idxd_device_evl_free+0xd5/0x100 [idxd] device_release_driver_internal+0x197/0x200 unbind_store+0xa1/0xb0 kernfs_fop_write_iter+0x120/0x1c0 vfs_write+0x2d3/0x400 ksys_write+0x63/0xe0 do_syscall_64+0x44/0xa0 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Move it out of the context. Fixes: 244da66cda35 ("dmaengine: idxd: setup event log configuration") Signed-off-by: Rex Zhang <rex.zhang@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> --- drivers/dma/idxd/device.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)