linux-kernel - Re: [RFC PATCH v10 0/5] fix vt-d hard lockup when hotplug ATS capable device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Thu, 18 Jan 2024 08:46:50 +0800
From: Baolu Lu <baolu.lu@...ux.intel.com>
To: Ethan Zhao <haifeng.zhao@...ux.intel.com>, kevin.tian@...el.com,
 bhelgaas@...gle.com, dwmw2@...radead.org, will@...nel.org,
 robin.murphy@....com, lukas@...ner.de
Cc: baolu.lu@...ux.intel.com, linux-pci@...r.kernel.org,
 iommu@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH v10 0/5] fix vt-d hard lockup when hotplug ATS capable
 device

On 1/17/24 5:00 PM, Ethan Zhao wrote:
> +       /*
> +        * If the ATS invalidation target device is gone this moment 
> (surprise
> +        * removed, died, no response) don't try this request again. this
> +        * request will not get valid result anymore. but the request was
> +        * already submitted to hardware and we predict to get a ITE in
> +        * followed batch of request, if so, it will get handled then.
> +        */
> +       if (target_pdev && !pci_device_is_present(target_pdev))
> +               return -EINVAL;

Again, we should not ignore the error triggered by the current request.
Do not leave it to the next one. The WAIT descriptor is a fence. Handle
everything within its boundary.

Best regards,
baolu