Re: [PATCH] x86/pkeys: Disable PKU when XFEATURE_PKRU is missing

[Ingo Molnar <mingo@kernel.org>]

* Borislav Petkov <bp@alien8.de> wrote:

> On Wed, Mar 19, 2025 at 10:39:33PM +0100, Ingo Molnar wrote:
> > Note that silent quirks are counterproductive, as they don't give VM 
> > vendors any incentives to fix their VM for such bugs.
> > 
> > So I changed your quirk to be:
> 
> This fires on my Zen3 now :-P
> 
> [    2.411315] x86/cpu: User Mode Instruction Prevention (UMIP) activated
> [    2.415307] ------------[ cut here ]------------
> [    2.419306] [Firmware Bug]: Invalid XFEATURE_PKRU configuration.
> [    2.423307] WARNING: CPU: 0 PID: 0 at arch/x86/kernel/cpu/common.c:530 identify_cpu+0x82a/0x840
> [    2.427306] Modules linked in:
> [    2.431307] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.14.0-rc7+ #1 PREEMPT(full) 
> [    2.435306] Hardware name: Micro-Star International Co., Ltd. MS-7A38/B450M PRO-VDH MAX (MS-7A38), BIOS B.G0 07/26/2022
> [    2.439306] RIP: 0010:identify_cpu+0x82a/0x840
> [    2.443306] Code: e8 bb f2 ff ff e9 4f ff ff ff 80 3d 07 4e 7b 01 00 0f 85 af fb ff ff 48 c7 c7 a8 fd f0 81 c6 05 f3 4d 7b 01 01 e8 e6 49 04 00 <0f> 0b e9 95 fb ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00
> [    2.447306] RSP: 0000:ffffffff82203ec8 EFLAGS: 00010296
> [    2.451306] RAX: 0000000000000034 RBX: 0000000000000000 RCX: 0000000000000000
> [    2.455306] RDX: 0000000080000003 RSI: 00000000ffffffea RDI: 0000000000000001
> [    2.459306] RBP: ffffffff82a09f40 R08: ffff88883e1fafe8 R09: 000000000027fffb
> [    2.463306] R10: 00000000000000ee R11: ffff88883d5fb000 R12: 0000000000000000
> [    2.467306] R13: ffff88883f373180 R14: ffffffff8220ba78 R15: 000000000008b000
> [    2.471306] FS:  0000000000000000(0000) GS:ffff88889742b000(0000) knlGS:0000000000000000
> [    2.475306] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    2.479306] CR2: ffff88883f1ff000 CR3: 000000000221a000 CR4: 00000000003108b0
> [    2.483306] Call Trace:
> [    2.487307]  <TASK>
> [    2.489459]  ? __warn+0x85/0x150
> [    2.491306]  ? identify_cpu+0x82a/0x840
> [    2.495306]  ? report_bug+0x1c3/0x1d0
> [    2.499306]  ? identify_cpu+0x82a/0x840
> [    2.503306]  ? identify_cpu+0x82c/0x840
> [    2.507306]  ? handle_bug+0xec/0x120
> [    2.511306]  ? exc_invalid_op+0x14/0x70
> [    2.515306]  ? asm_exc_invalid_op+0x16/0x20
> [    2.519306]  ? identify_cpu+0x82a/0x840
> [    2.523306]  ? identify_cpu+0x82a/0x840
> [    2.527306]  arch_cpu_finalize_init+0x23/0x150
> [    2.531307]  start_kernel+0x40a/0x720
> [    2.535306]  x86_64_start_reservations+0x14/0x30
> [    2.539306]  x86_64_start_kernel+0xa8/0xc0
> [    2.543306]  common_startup_64+0x12c/0x138
> [    2.547307]  </TASK>
> [    2.551306] ---[ end trace 0000000000000000 ]---
> 
> Zapping it for the time being.

Thanks!

	Ingo