Re: [PATCH] pci_regs: reintroduce PCI_MSIX_FLAGS_BIRMASK

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Jul 14, 2015 at 06:29:24PM -0500, Bjorn Helgaas wrote:
> On Mon, Jul 13, 2015 at 06:11:38PM +0300, Michael S. Tsirkin wrote:
> > On Wed, Jul 01, 2015 at 12:14:10PM +0200, Michael S. Tsirkin wrote:
> > > This partially reverts commit 09a2c73ddfc7f173237fc7209a65b34dd5bcb5ed.
> > >     PCI: Remove unused PCI_MSIX_FLAGS_BIRMASK definition
> > > 
> > > That commit dropped a symbol from an exported header claiming "no one
> > > uses it". This isn't how Linux normally approaches userspace API though,
> > > and in fact QEMU build fails if trying to use updated headers from linux
> > > 3.12 and up.
> > > 
> > > Sure, userspace can be fixed to use the new symbol, but the cost
> > > of keeping the old one around is fairly low, too.
> > > 
> > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> 
> Sorry, I lost the original message somehow, so I can't reply to it.  I
> applied this by hand to my for-linus branch for v4.2, thanks!



Did you mean 4.2? time's running out on this one ...
Just making sure - it's still not upstream, right?


> 
> commit c9ddbac9c89110f77cb0fa07e634aaf1194899aa
> Author: Michael S. Tsirkin <mst@redhat.com>
> Date:   Tue Jul 14 18:27:46 2015 -0500
> 
>     PCI: Restore PCI_MSIX_FLAGS_BIRMASK definition
>     
>     09a2c73ddfc7 ("PCI: Remove unused PCI_MSIX_FLAGS_BIRMASK definition")
>     removed PCI_MSIX_FLAGS_BIRMASK from an exported header because it was
>     unused in the kernel.  But that breaks user programs that were using it
>     (QEMU in particular).
>     
>     Restore the PCI_MSIX_FLAGS_BIRMASK definition.
>     
>     [bhelgaas: changelog]
>     Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
>     Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
>     CC: stable@vger.kernel.org	# v3.13+
> 
> diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
> index efe3443..413417f 100644
> --- a/include/uapi/linux/pci_regs.h
> +++ b/include/uapi/linux/pci_regs.h
> @@ -319,6 +319,7 @@
>  #define PCI_MSIX_PBA		8	/* Pending Bit Array offset */
>  #define  PCI_MSIX_PBA_BIR	0x00000007 /* BAR index */
>  #define  PCI_MSIX_PBA_OFFSET	0xfffffff8 /* Offset into specified BAR */
> +#define PCI_MSIX_FLAGS_BIRMASK	PCI_MSIX_PBA_BIR /* deprecated */
>  #define PCI_CAP_MSIX_SIZEOF	12	/* size of MSIX registers */
>  
>  /* MSI-X Table entry format */