On Thu, Aug 12, 2021 at 6:17 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>
> [+to Greg, please update sysfs_defferred_iomem_get_mapping-5.15]
>
> On Thu, Aug 12, 2021 at 01:21:44PM +0000, Krzysztof Wilczyński wrote:
> > Two legacy PCI sysfs objects "legacy_io" and "legacy_mem" were updated
> > to use an unified address space in the commit 636b21b50152 ("PCI: Revoke
> > mappings like devmem"). This allows for revocations to be managed from
> > a single place when drivers want to take over and mmap() a /dev/mem
> > range.
> >
> > Following the update, both of the sysfs objects should leverage the
> > iomem_get_mapping() function to get an appropriate address range, but
> > only the "legacy_io" has been correctly updated - the second attribute
> > seems to be using a wrong variable to pass the iomem_get_mapping()
> > function to.
> >
> > Thus, correct the variable name used so that the "legacy_mem" sysfs
> > object would also correctly call the iomem_get_mapping() function.
> >
> > Fixes: 636b21b50152 ("PCI: Revoke mappings like devmem")
> > Signed-off-by: Krzysztof Wilczyński <kw@xxxxxxxxx>
>
> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>
> Ouch. This needs to be applied to any -stable trees that contain
> 636b21b50152, which was merged in v5.12.
Ouch indeed. Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
>
> It *also* needs to be applied with the obvious updates to Greg's
> sysfs_defferred_iomem_get_mapping-5.15 branch because it was changed
> by f06aff924f97 ("sysfs: Rename struct bin_attribute member to
> f_mapping") [1]
>
> [1] https://git.kernel.org/cgit/linux/kernel/git/gregkh/driver-core.git/commit/?id=f06aff924f97
>
> > ---
> > drivers/pci/pci-sysfs.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> > index 5d63df7c1820..7bbf2673c7f2 100644
> > --- a/drivers/pci/pci-sysfs.c
> > +++ b/drivers/pci/pci-sysfs.c
> > @@ -978,7 +978,7 @@ void pci_create_legacy_files(struct pci_bus *b)
> > b->legacy_mem->size = 1024*1024;
> > b->legacy_mem->attr.mode = 0600;
> > b->legacy_mem->mmap = pci_mmap_legacy_mem;
> > - b->legacy_io->mapping = iomem_get_mapping();
> > + b->legacy_mem->mapping = iomem_get_mapping();
> > pci_adjust_legacy_attr(b, pci_mmap_mem);
> > error = device_create_bin_file(&b->dev, b->legacy_mem);
> > if (error)
> > --
> > 2.32.0
> >
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
