This is a note to let you know that I've just added the patch titled
x86/pci/xen: Fix PCIBIOS_* return code handling
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-pci-xen-fix-pcibios_-return-code-handling.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f2ef1bfb843d1c03d4e4f7fc37ecb10b5a05fc20
Author: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Date: Mon May 27 15:55:37 2024 +0300
x86/pci/xen: Fix PCIBIOS_* return code handling
[ Upstream commit e9d7b435dfaec58432f4106aaa632bf39f52ce9f ]
xen_pcifront_enable_irq() uses pci_read_config_byte() that returns
PCIBIOS_* codes. The error handling, however, assumes the codes are
normal errnos because it checks for < 0.
xen_pcifront_enable_irq() also returns the PCIBIOS_* code back to the
caller but the function is used as the (*pcibios_enable_irq) function
which should return normal errnos.
Convert the error check to plain non-zero check which works for
PCIBIOS_* return codes and convert the PCIBIOS_* return code using
pcibios_err_to_errno() into normal errno before returning it.
Fixes: 3f2a230caf21 ("xen: handled remapped IRQs when enabling a pcifront PCI device.")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Link: https://lore.kernel.org/r/20240527125538.13620-3-ilpo.jarvinen@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index bacf8d988f65f..d308057aec0b9 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -36,10 +36,10 @@ static int xen_pcifront_enable_irq(struct pci_dev *dev)
u8 gsi;
rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
- if (rc < 0) {
+ if (rc) {
dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n",
rc);
- return rc;
+ return pcibios_err_to_errno(rc);
}
/* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/
pirq = gsi;
