From: Pali Rohár <pali@kernel.org> stable inclusion from stable-v5.10.94 commit 2a0d437d8a76474452cb91d2fc729020c2371ad3 bugzilla: https://gitee.com/openeuler/kernel/issues/I531X9 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 1c1a3b4d3e86b997a313ffb297c1129540882859 upstream. If expansion ROM is unsupported (which is the case of pci-bridge-emul.c driver) then ROM Base Address register must be implemented as read-only register that return 0 when read, same as for unused Base Address registers. Link: https://lore.kernel.org/r/20211124155944.1290-2-pali@kernel.org Fixes: 23a5fba4d941 ("PCI: Introduce PCI bridge emulated config space common logic") Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Acked-by: Xie XiuQi <xiexiuqi@huawei.com> --- drivers/pci/pci-bridge-emul.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c index db97cddfc85e..5de8b8dde209 100644 --- a/drivers/pci/pci-bridge-emul.c +++ b/drivers/pci/pci-bridge-emul.c @@ -139,8 +139,13 @@ struct pci_bridge_reg_behavior pci_regs_behavior[PCI_STD_HEADER_SIZEOF / 4] = { .ro = GENMASK(7, 0), }, + /* + * If expansion ROM is unsupported then ROM Base Address register must + * be implemented as read-only register that return 0 when read, same + * as for unused Base Address registers. + */ [PCI_ROM_ADDRESS1 / 4] = { - .rw = GENMASK(31, 11) | BIT(0), + .ro = ~0, }, /* -- 2.20.1