On Fri, Sep 25 2020 at 17:49, Peter Zijlstra wrote:

Here it looks like this:

[    1.830276] BUG: kernel NULL pointer dereference, address: 0000000000000000
[    1.838043] #PF: supervisor instruction fetch in kernel mode
[    1.844357] #PF: error_code(0x0010) - not-present page
[    1.850090] PGD 0 P4D 0
[    1.852915] Oops: 0010 [#1] SMP
[    1.856419] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc6-00700-g0248dedd12d4 #419
[    1.865447] Hardware name: Intel Corporation S2600GZ/S2600GZ, BIOS SE5C600.86B.02.02.0002.122320131210 12/23/2013
[    1.876902] RIP: 0010:0x0
[    1.879824] Code: Bad RIP value.
[    1.883423] RSP: 0000:ffffffff82803da0 EFLAGS: 00010282
[    1.889251] RAX: 0000000000000000 RBX: ffffffff8282b980 RCX: ffffffff82803e40
[    1.897241] RDX: 0000000000000001 RSI: ffffffff82803e40 RDI: ffffffff8282b980
[    1.905201] RBP: ffff88842f331000 R08: 00000000ffffffff R09: 0000000000000001
[    1.913162] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000048
[    1.921123] R13: ffffffff82803e40 R14: ffffffff8282b9c0 R15: 0000000000000000
[    1.929085] FS:  0000000000000000(0000) GS:ffff88842f400000(0000) knlGS:0000000000000000
[    1.938113] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.944524] CR2: ffffffffffffffd6 CR3: 0000000002811001 CR4: 00000000000606b0
[    1.952484] Call Trace:
[    1.955214]  msi_domain_alloc+0x36/0x130

Hrm. That looks like a not initialized mandatory callback. Confused.

Is this on -next and if so, does this happen on tip:x86/irq as well?

Can you provide yoru config please?

Thanks,

        tglx