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@xxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
---
Reviewed-by: Lijun Pan <lijun.pan@xxxxxxxxx>
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)
