Greeting,

FYI, we noticed the following commit (built with gcc-9):

commit: b643128b917ca8f1c8b1e14af64ebdc81147b2d1 ("x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomain")
https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git x86/apic


in testcase: nvml
version: nvml-x86_64-9a558d859-1_20201008
with following parameters:

	test: pmem
	group: unicode
	nr_pmem: 1
	fs: ext4
	mount_option: dax
	bp_memmap: 32G!4G
	ucode: 0x7000019



on test machine: 16 threads Intel(R) Xeon(R) CPU D-1541 @ 2.10GHz with 48G memory

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):

If you fix the issue, kindly add following tag
Reported-by: kernel test robot <oliver.sang@intel.com>

[    3.148819] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
[    3.154825] DMAR: DRHD: handling fault status reg 2
[    3.159701] DMAR: [INTR-REMAP] Request device [f0:1f.7] fault index 0 [fault reason 37] Blocked a compatibility format interrupt request
[    3.173870] Kernel panic - not syncing: timer doesn't work through Interrupt-remapped IO-APIC
[    3.182381] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc1-00029-gb643128b917c #1
[    3.190370] Hardware name: Supermicro SYS-5018D-FN4T/X10SDV-8C-TLN4F, BIOS 1.1 03/02/2016
[    3.198534] Call Trace:
[    3.200983]  dump_stack+0x57/0x6a
[    3.204298]  panic+0x102/0x2d2
[    3.207349]  panic_if_irq_remap.cold+0x5/0x5
[    3.211613]  check_timer+0x1f6/0x694
[    3.215184]  ? printk+0x58/0x6f
[    3.218320]  setup_IO_APIC+0x17b/0x1c3
[    3.222067]  x86_late_time_init+0x20/0x30
[    3.226077]  start_kernel+0x40c/0x4c7
[    3.229734]  secondary_startup_64_no_verify+0xb8/0xbb

To reproduce:

        git clone https://github.com/intel/lkp-tests.git
        cd lkp-tests
        bin/lkp install job.yaml  # job file is attached in this email
        bin/lkp run     job.yaml



Thanks,
Oliver Sang