linux-kernel - Re: [PATCH V2] PCI: Fix PCI bridges not to go to D3Hot on SPARC64

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: <541bb4f91ab1d4145a2bd2891546649a9ed3ec4d.camel@physik.fu-berlin.de>
Date: Wed, 03 Dec 2025 20:31:58 +0100
From: John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>
To: René Rebe <rene@...ctco.de>, linux-pci@...r.kernel.org
Cc: rafael@...nel.org, mika.westerberg@...ux.intel.com, lukas@...ner.de, 
	briannorris@...omium.org, helgaas@...nel.org, linux-kernel@...r.kernel.org,
 	riccardo.mottola@...ero.it, mani@...nel.org, mario.limonciello@....com
Subject: Re: [PATCH V2] PCI: Fix PCI bridges not to go to D3Hot on SPARC64

Hi Rene,

On Wed, 2025-12-03 at 20:05 +0100, René Rebe wrote:
> Commit a5fb3ff63287 ("PCI: Allow PCI bridges to go to D3Hot on all
> non-x86") was bisected to break some SPARC64 systems, see two oopses
> below. Fix by not allowing D3Hot on sparc64 while this is being
> further analyzed.

I think your summary is still misleading as at least to me it sounds
like you are providing a patch that fixes the D3Hot state on SPARC64
while in reality you're actually blacklisting the D3 power state on
the platform.

I suggest something like:

"pci: Don't allow D3 power state on sparc64"

This would also match the description of pci_bridge_d3_possible():

/**
 * pci_bridge_d3_possible - Is it possible to put the bridge into D3
 * @bridge: Bridge to check
 *
 * Currently we only allow D3 for some PCIe ports and for Thunderbolt.
 *
 * Return: Whether it is possible to move the bridge to D3.
 *
 * The return value is guaranteed to be constant across the entire lifetime
 * of the bridge, including its hot-removal.
 */

The function pci_bridge_d3_possible() determines whether D3 is allowed
on a certain platform and by adding CONFIG_SPARC64 to the list, you are
explicitly disallowing the use of this power state.

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913