[PATCH] PCI: mvebu: Mark driver as BROKEN

[Pali Rohár]

On Friday 04 August 2023 15:46:22 Uwe Kleine-König wrote:
> [Cc += linux-arm-kernel list]
> 
> On Fri, Aug 04, 2023 at 12:35:13PM +0100, Russell King (Oracle) wrote:
> > So it seems this patch got applied, but it wasn't Cc'd to
> > linux-arm-kernel or anyone else, so those of us with platforms never
> > had a chance to comment on it.
> > 
> > *** This change causes a regression to working setups. ***
> > 
> > It appears that the *only* reason this patch was proposed is to stop a
> > kernel developer receiving problem reports from a set of users, but
> > completely ignores that there is another group of users where this works
> > fine - and thus the addition of this patch causes working setups to
> > regress.
> > 
> > Because one is being bothered with problem reports is not a reason to
> > mark a driver broken - and especially not doing so in a way that those
> > who may be affected don't get an opportunity to comment on the patch!
> > Also, there is _zero_ information provided on what the reported problems
> > actually are, so no one else can guess what these issues are.
> > 
> > However, given that there are working setups and this change causes
> > those to regress, it needs to be reverted.
> > 
> > For example, I have an Atheros PCIe WiFi card in an Armada 388 Clearfog
> > platform, and this works fine.
> > 
> > Uwe has a SATA controller for a bunch of disks in an Armada 370 based
> > NAS platform that is connected to PCIe, and removing PCIe support
> > effectively makes his platform utterly useless.
> 
> While this is true there is really a problem on my platform with
> accessing the hard disks via that pci controller and a 88SE9215 SATA
> controller. While it seems to work in principle, it's incredible slow.

Exactly those are things which randomly does not work.

> I intend to bisect that, 6.1.x is still fine. Don't know when I find the
> time though, as there are a few things that are more important
> currently.
> 
> +1 on some information about what is already known about the breakage.
> 
> > Please revert this patch.
> > 
> > Thanks.
> > 
> > On Sat, Jan 14, 2023 at 05:41:25PM +0100, Pali Rohár wrote:
> > > People are reporting that pci-mvebu.c driver does not work with recent
> > > mainline kernel. There are more bugs which prevents its for daily usage.
> > > So lets mark it as broken for now, until somebody would be able to fix it
> > > in mainline kernel.
> > > 
> > > Signed-off-by: Pali Rohár <pali at kernel.org>
> > > 
> > > ---
> > > Bjorn: I would really appreciate if you take this change and send it in
> > > pull request for v6.2 release. There is no reason to wait more longer.
> > > 
> > > 
> > > I'm periodically receiving emails that driver does not work correctly
> > > anymore, PCIe cards are not detected or that they crashes during boot.
> > > 
> > > Some of the issues are handled in patches which are waiting on the list for
> > > a long time and nobody cares for them. Some others needs investigation.
> > > 
> > > I'm really tired in replying to those user emails as I cannot do more in
> > > this area. I have asked more people for help but either there were only
> > > promises without any action for more than year or simple no direction how
> > > to move forward or what to do with it.
> > > 
> > > So mark this driver as broken. Users would see the real current state
> > > and hopefully will stop reporting me old or new bugs.
> > > ---
> > >  drivers/pci/controller/Kconfig | 1 +
> > >  1 file changed, 1 insertion(+)
> > > 
> > > diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
> > > index 1569d9a3ada0..b4a4d84a358b 100644
> > > --- a/drivers/pci/controller/Kconfig
> > > +++ b/drivers/pci/controller/Kconfig
> > > @@ -9,6 +9,7 @@ config PCI_MVEBU
> > >  	depends on MVEBU_MBUS
> > >  	depends on ARM
> > >  	depends on OF
> > > +	depends on BROKEN
> > >  	select PCI_BRIDGE_EMUL
> > >  	help
> > >  	 Add support for Marvell EBU PCIe controller. This PCIe controller
> > > -- 
> > > 2.20.1
> > > 
> > 
> > -- 
> > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> > FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
> > 
> 
> -- 
> Pengutronix e.K.                           | Uwe Kleine-König            |
> Industrial Linux Solutions                 | https://www.pengutronix.de/ |