PCI: hv: Fix hv_arch_irq_unmask() for multi-MSI
stable inclusion from stable-v5.10.134 commit 73bf070408a7f07e813ab26ebde1b09fca159cd6 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ZVR7 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=73bf070408a7f07e813ab26ebde1b09fca159cd6 -------------------------------- commit 455880df upstream. In the multi-MSI case, hv_arch_irq_unmask() will only operate on the first MSI of the N allocated. This is because only the first msi_desc is cached and it is shared by all the MSIs of the multi-MSI block. This means that hv_arch_irq_unmask() gets the correct address, but the wrong data (always 0). This can break MSIs. Lets assume MSI0 is vector 34 on CPU0, and MSI1 is vector 33 on CPU0. hv_arch_irq_unmask() is called on MSI0. It uses a hypercall to configure the MSI address and data (0) to vector 34 of CPU0. This is correct. Then hv_arch_irq_unmask is called on MSI1. It uses another hypercall to configure the MSI address and data (0) to vector 33 of CPU0. This is wrong, and results in both MSI0 and MSI1 being routed to vector 33. Linux will observe extra instances of MSI1 and no instances of MSI0 despite the endpoint device behaving correctly. For the multi-MSI case, we need unique address and data info for each MSI, but the cached msi_desc does not provide that. However, that information can be gotten from the int_desc cached in the chip_data by compose_msi_msg(). Fix the multi-MSI case to use that cached information instead. Since hv_set_msi_entry_from_desc() is no longer applicable, remove it. 5.10 backport - removed unused hv_set_msi_entry_from_desc function from mshyperv.h instead of pci-hyperv.c. msi_entry.address/data.as_uint32 changed to direct reference (as they are u32's, just sans union). Signed-off-by:Jeffrey Hugo <quic_jhugo@quicinc.com> Reviewed-by:
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