On Thu, Sep 24, 2020 at 10:34:21PM -0400, Ethan Zhao wrote: > During DPC error injection test we found there is race condition between > pciehp and DPC driver, null pointer reference caused panic as following null -> NULL > > # setpci -s 64:02.0 0x196.w=000a > // 64:02.0 is rootport has DPC capability > # setpci -s 65:00.0 0x04.w=0544 > // 65:00.0 is NVMe SSD populated in above port > # mount /dev/nvme0n1p1 nvme > > (tested on stable 5.8 & ICX platform) > > Buffer I/O error on dev nvme0n1p1, logical block 468843328, > async page read > BUG: kernel NULL pointer dereference, address: 0000000000000050 > #PF: supervisor read access in kernel mode > #PF: error_code(0x0000) - not-present page Same comment about Oops. -- With Best Regards, Andy Shevchenko