linux-kernel - Re: [PATCH v3 26/30] drivers: hv: dxgkrnl: Offer and reclaim allocations

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:   Wed, 2 Mar 2022 14:25:17 +0000
From:   Wei Liu <wei.liu@...nel.org>
To:     Iouri Tarassov <iourit@...ux.microsoft.com>
Cc:     kys@...rosoft.com, haiyangz@...rosoft.com, sthemmin@...rosoft.com,
        wei.liu@...nel.org, linux-hyperv@...r.kernel.org,
        linux-kernel@...r.kernel.org, spronovo@...rosoft.com,
        spronovo@...ux.microsoft.com, gregkh@...uxfoundation.org
Subject: Re: [PATCH v3 26/30] drivers: hv: dxgkrnl: Offer and reclaim
 allocations

On Tue, Mar 01, 2022 at 11:46:13AM -0800, Iouri Tarassov wrote:
> Implement ioctls to offer and reclaim compute device allocations:
>   - LX_DXOFFERALLOCATIONS,
>   - LX_DXRECLAIMALLOCATIONS2
> 
> When a user mode driver (UMD) does not need to access an allocation,

What is a "user mode driver" in this context? Is that something that
runs inside the guest?

> it can "offer" it by issuing the LX_DXOFFERALLOCATIONS ioctl.  This
> means that the allocation is not in use and its local device memory
> could be evicted. The freed space could be given to another allocation.
> When the allocation is again needed, the UMD can attempt to"reclaim"
> the allocation by issuing the LX_DXRECLAIMALLOCATIONS2 ioctl. If the
> allocation is still not evicted, the reclaim operation succeeds and no
> other action is required. If the reclaim operation fails, the caller
> must restore the content of the allocation before it can be used by
> the device.
> 
> Signed-off-by: Iouri Tarassov <iourit@...ux.microsoft.com>