Re: "irq/matrix: Spread interrupts on allocation" breaks nouveau in mainline kernel

[Borislav Petkov]

On Wed, Jan 24, 2018 at 01:50:52PM +0100, Thomas Gleixner wrote:
> On Tue, 23 Jan 2018, Lyude Paul wrote:
> 
> > Hi! Sorry to be the bearer of bad news, but this patch actually seems to break
> > suspending and resuming with nouveau on my machine:
> 
> > [   31.003578] WARNING: CPU: 0 PID: 11523 at kernel/smp.c:291
> > smp_call_function_single+0xdc/0xe0
> 
> This warning has absolutely no relationship to that patch.
> 
> > [   31.003592] RIP: 0010:smp_call_function_single+0xdc/0xe0
> > [   31.003603]  ? rdmsr_safe_on_cpu+0x4b/0x70
> > [   31.003604]  rdmsr_safe_on_cpu+0x4b/0x70
> > [   31.003606]  get_block_address.isra.0+0x6e/0xe0
> > [   31.003607]  mce_amd_feature_init+0x63/0x2c0
> > [   31.003609]  mce_syscore_resume+0x1e/0x30
> > [   31.003611]  syscore_resume+0x4b/0x170
> > [   31.003613]  suspend_devices_and_enter+0x608/0x7e0
> > [   31.003614]  pm_suspend+0x315/0x380
> > [   31.003615]  state_store+0x7d/0xe0
> > [   31.003618]  kernfs_fop_write+0xfa/0x180
> > [   31.003620]  __vfs_write+0x23/0x130
> > [   31.003623]  ? SYSC_newfstat+0x29/0x40
> > [   31.003625]  ? _cond_resched+0x15/0x40
> > [   31.003626]  vfs_write+0xad/0x1a0
> > [   31.003627]  SyS_write+0x42/0x90
> > [   31.003629]  entry_SYSCALL_64_fastpath+0x24/0x87
> 
> Borislav?

Yeah

cfee4f6f0b20 ("x86/mce/AMD: Read MSRs on the CPU allocating the threshold blocks")

Yazen CCed.

Non-core banks are accessible only on the node-base CPU or something
like that. But we can't send IPIs with IRQs off, thus the warning.

Yazen, I'm thinking this whole get_block_address() dancing can be
simplified by creating a data structure containing *all* MCi_MISC*
addresses once during boot and then using it instead of reading it from
the MSRs each time.

Also - and I'm wishfully thinking simple here - that structure could
be global as I'd venture a guess that all MISC addresses are the same
system-wide and not node-specific.

But I might be missing something here.

Hmmm.

-- 
Regards/Gruss,
    Boris.

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