Re: [PATCH 1/2] i2c: piix4: Use request_muxed_region

[Guenter Roeck]

On 02/13/2018 03:48 AM, Böszörményi Zoltán wrote:
> 2018-02-12 19:51 keltezéssel, Guenter Roeck írta:
> > On Mon, Feb 12, 2018 at 11:10:41AM +0100, Jean Delvare wrote:
> > > Hi Guneter,
> > >
> > > Sorry for the delay :(
> > >
> > > On Sat, 30 Dec 2017 08:50:57 -0800, Guenter Roeck wrote:
> > > > Accesses to SB800_PIIX4_SMB_IDX can occur from multiple drivers.
> > > > Use request_muxed_region() to ensure synchronization.
> > >
> > > Which ones? Documenting it, at least in the commit message, would seem
> > > useful. Out of curiosity, have these other drivers been converted to
> > > use request_muxed_region already?
> > Primarily watchdog, but there is also unprotected initialization code
> > in several locations.
>
> There are three locations touching the same I/O ports:
> the PCI-USB quirks code (still doesn't use locking AFAIK), i2c-piix4 and
> the sp5100_tco watchdog drivers.

There are a few more in arch code, though probably not all of those (or maybe none ?)
are relevant.

arch/x86/kernel/quirks.c
arch/x86/kernel/early-quirks.c
arch/x86/pci/fixup.c
arch/mips/loongson64/loongson-3/acpi_init.c
drivers/usb/host/pci-quirks.c
drivers/watchdog/sp5100_tco.[ch]
drivers/i2c/busses/i2c-piix4.c

Guenter