linux-kernel - Re: [PATCH v4 1/2] USB: core: add a memory pool to urb caching host-controller private data

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]

Message-ID: <2ffd5bed.9108.196f763d60d.Coremail.00107082@163.com>
Date: Thu, 22 May 2025 17:47:17 +0800 (CST)
From: "David Wang" <00107082@....com>
To: "Greg KH" <gregkh@...uxfoundation.org>, mathias.nyman@...el.com,
	oneukum@...e.com, stern@...land.harvard.edu
Cc: linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 1/2] USB: core: add a memory pool to urb caching
 host-controller private data


At 2025-05-22 16:33:42, "Greg KH" <gregkh@...uxfoundation.org> wrote:
>On Thu, May 22, 2025 at 03:09:43PM +0800, David Wang wrote:
>> From an end-user's perspective, the performance difference with this change
>> is insignificant when system is under no memory pressure, and when under
>> heavy memory pressure. When system is under heavy memory pressure,
>> everything is slow.  There could be a point in-between no memory pressure
>> and heavy memory pressure where these 1k+/s memory allocations would
>> dominate the performance, but very hard to pinpoint it.
>
>For this reason alone I can't take this change, sorry.

Still, reasonable to me....
>
>Also, as others have stated, this could be done in the hcd drivers
>themselves if they want to, no need to push this into the usb core.


>
>thanks,
>
>greg k-h


Thanks all you guys for taking time reviewing/discussing this.

David