From: Michael Ellerman mpe@ellerman.id.au
stable inclusion from stable-v5.10.137 commit cadeb5186e253ba9e44284423621090f1e2420e6 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit f4b39e88b42d13366b831270306326b5c20971ca ]
The recent change to the PHB numbering logic has a logic error in the handling of "ibm,opal-phbid".
When an "ibm,opal-phbid" property is present, &prop is written to and ret is set to zero.
The following call to of_alias_get_id() is skipped because ret == 0.
But then the if (ret >= 0) is true, and the body of that if statement sets prop = ret which throws away the value that was just read from "ibm,opal-phbid".
Fix the logic by only doing the ret >= 0 check in the of_alias_get_id() case.
Fixes: 0fe1e96fef0a ("powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias") Reviewed-by: Pali Rohár pali@kernel.org Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20220802105723.1055178-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- arch/powerpc/kernel/pci-common.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 7af00a880e16..f9d35c9ea4ae 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -89,11 +89,13 @@ static int get_phb_number(struct device_node *dn) } if (ret) ret = of_property_read_u64(dn, "ibm,opal-phbid", &prop); - if (ret) + + if (ret) { ret = of_alias_get_id(dn, "pci"); - if (ret >= 0) { - prop = ret; - ret = 0; + if (ret >= 0) { + prop = ret; + ret = 0; + } } if (ret) { u32 prop_32;