4.19-stable review patch. If anyone has any objections, please let me know.
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From: Ilpo Järvinen ilpo.jarvinen@linux.intel.com
[ 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@linux.intel.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Reviewed-by: Juergen Gross jgross@suse.com Link: https://lore.kernel.org/r/20240527125538.13620-3-ilpo.jarvinen@linux.intel.c... Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/pci/xen.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
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;