Re: [PATCH 0/5] iommu/amd: fixes for suspend/resume

From: Mike Lothian <mike@fireburn.co.uk>
To: Maxim Levitsky <mlevitsk@redhat.com>
Cc: dwmw@amazon.co.uk, iommu@lists.linux-foundation.org,
	joro@8bytes.org, linux-kernel@vger.kernel.org,
	suravee.suthikulpanit@amd.com, tglx@linutronix.de,
	will@kernel.org
Subject: Re: [PATCH 0/5] iommu/amd: fixes for suspend/resume
Date: Tue, 25 Jan 2022 23:25:50 +0000	[thread overview]
Message-ID: <CAHbf0-FJ0c1yAumKCnXLKKFN=tzeJxSd3HyP=dUOBgBTxVG5fw@mail.gmail.com> (raw)
In-Reply-To: <6f0d9b07073ca6d3657500ec076edc1ad2a3e40a.camel@redhat.com>

On Tue, 25 Jan 2022 at 19:26, Maxim Levitsky <mlevitsk@redhat.com> wrote:
>
> Could you just apply these patches on top of 5.15 kernel and see if you get the warning?
>
> If something could case it is I think patch 1, it does move the GA log enabled
> to be a bit later.
> I also added few warnings there. I wonder why your dmesg quote doesn't contain the C line
> where the warning happens.
>
> In partucular I added:
>
> if (WARN_ON(status & (MMIO_STATUS_GALOG_RUN_MASK)))
>
> That will fire if GA log is already running (maybe BIOS enabled it? - it really shouldn't do that)
>
>
> And that:
>
> if (WARN_ON(i >= LOOP_TIMEOUT))
>
> also should not happen and worth to be logged IMHO.
>
> Best regards,
>         Maxim Levitsky
>

Hi

I applied on top of another kernel as you asked, I also enabled some debugging

[    0.398833] ------------[ cut here ]------------
[    0.398835] WARNING: CPU: 0 PID: 1 at drivers/iommu/amd/init.c:839
amd_iommu_enable_interrupts+0x1da/0x440
[    0.398840] Modules linked in:
[    0.398841] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.16.0-rc5-agd5f+ #1388
[    0.398843] Hardware name: ASUSTeK COMPUTER INC. ROG Strix
G513QY_G513QY/G513QY, BIOS G513QY.316 11/29/2021
[    0.398845] RIP: 0010:amd_iommu_enable_interrupts+0x1da/0x440
[    0.398847] Code: 4b 38 48 89 41 18 b8 a0 86 01 00 0f 1f 44 00 00
48 8b 4b 38 8b 89 20 20 00 00 f7 c1 00 01 00 00 0f 85 7a fe ff ff ff
c8 75 e6 <0f> 0b e9 6f fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44
0
0 00
[    0.398850] RSP: 0018:ffff888100927c68 EFLAGS: 00010246
[    0.398851] RAX: 0000000000000000 RBX: ffff88810004b000 RCX: 0000000000000018
[    0.398853] RDX: 0000000000000008 RSI: ffff888100927c70 RDI: ffffc900000800f0
[    0.398854] RBP: ffff888100927c68 R08: ffff8881015b8f88 R09: 0000000000000000
[    0.398855] R10: 0000000000000000 R11: ffffffffffffffff R12: ffffffff7fffffff
[    0.398856] R13: 0000777f80000000 R14: 0000000000000000 R15: ffffffff8357a758
[    0.398858] FS:  0000000000000000(0000) GS:ffff888fde400000(0000)
knlGS:0000000000000000
[    0.398859] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.398860] CR2: 0000000000000000 CR3: 00000000ac40c000 CR4: 0000000000150ef0
[    0.398862] Call Trace:
[    0.398864]  <TASK>
[    0.398864]  ? iommu_setup+0x29a/0x29a
[    0.398867]  ? state_next+0x6e/0x1c9
[    0.398870]  ? iommu_setup+0x29a/0x29a
[    0.398872]  ? iommu_go_to_state+0x1f/0x33
[    0.398873]  ? amd_iommu_init+0xa/0x23
[    0.398875]  ? pci_iommu_init+0xf/0x45
[    0.398876]  ? iommu_setup+0x29a/0x29a
[    0.398878]  ? __initstub__kmod_pci_dma__244_136_pci_iommu_initrootfs+0x5/0x8
[    0.398880]  ? do_one_initcall+0x100/0x290
[    0.398882]  ? do_initcall_level+0x8b/0xe5
[    0.398884]  ? do_initcalls+0x44/0x6d
[    0.398885]  ? kernel_init_freeable+0xc7/0x10d
[    0.398886]  ? rest_init+0xc0/0xc0
[    0.398888]  ? kernel_init+0x11/0x150
[    0.398889]  ? ret_from_fork+0x22/0x30
[    0.398891]  </TASK>
[    0.398892] ---[ end trace f048a4ec907dc976 ]---

Which points to patch one and "if (WARN_ON(i >= LOOP_TIMEOUT))"

Hope that helps

Mike