Messages in this thread Patch in this message | | | From | Xiang Zheng <> | Subject | [PATCH] pci: lock the pci_cfg_wait queue for the consistency of data | Date | Mon, 28 Oct 2019 17:18:09 +0800 |
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Commit "7ea7e98fd8d0" suggests that the "pci_lock" is sufficient, and all the callers of pci_wait_cfg() are wrapped with the "pci_lock".
However, since the commit "cdcb33f98244" merged, the accesses to the pci_cfg_wait queue are not safe anymore. A "pci_lock" is insufficient and we need to hold an additional queue lock while read/write the wait queue.
So let's use the add_wait_queue()/remove_wait_queue() instead of __add_wait_queue()/__remove_wait_queue().
Signed-off-by: Xiang Zheng <zhengxiang9@huawei.com> Cc: Heyi Guo <guoheyi@huawei.com> Cc: Biaoxiang Ye <yebiaoxiang@huawei.com> Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com> --- drivers/pci/access.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 2fccb5762c76..247bf36e0047 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -207,14 +207,14 @@ static noinline void pci_wait_cfg(struct pci_dev *dev) { DECLARE_WAITQUEUE(wait, current); - __add_wait_queue(&pci_cfg_wait, &wait); + add_wait_queue(&pci_cfg_wait, &wait); do { set_current_state(TASK_UNINTERRUPTIBLE); raw_spin_unlock_irq(&pci_lock); schedule(); raw_spin_lock_irq(&pci_lock); } while (dev->block_cfg_access); - __remove_wait_queue(&pci_cfg_wait, &wait); + remove_wait_queue(&pci_cfg_wait, &wait); } /* Returns 0 on success, negative values indicate error. */ -- 2.19.1
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