Re: [PATCH] Hyper-V: pci: x64: Generalize irq/msi set-up and handling

From: Bjorn Helgaas
Date: Thu Jan 07 2021 - 10:03:02 EST


There seems to be a long tradition of dreaming up random formats for
the subject lines of Hyper-V-related patches. Look at all the
different ways these are spelled, hyphenated, and capitalized:

$ git log --oneline arch/x86/include/asm/mshyperv.h
626b901f6044 ("Drivers: hv: vmbus: Add parsing of VMbus interrupt in ACPI DSDT")
b9d8cf2eb3ce ("x86/hyperv: Make hv_setup_sched_clock inline")
a16be368dd3f ("x86/entry: Convert various hypervisor vectors to IDTENTRY_SYSVEC")
2ddddd0b4e89 ("Drivers: hv: Move AEOI determination to architecture dependent code")
1cf106d93245 ("PCI: hv: Introduce hv_msi_entry")
b95a8a27c300 ("x86/vdso: Use generic VDSO clock mode storage")
eec399dd8627 ("x86/vdso: Move VDSO clocksource state tracking to callback")
fa36dcdf8b20 ("x86: hv: Add function to allocate zeroed page for Hyper-V")
8c3e44bde7fd ("x86/hyperv: Add functions to allocate/deallocate page for Hyper-V")
765e33f5211a ("Drivers: hv: vmbus: Break out ISA independent parts of mshyperv.h")
dd2cb348613b ("clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic")
cc4edae4b924 ("x86/hyper-v: Add HvFlushGuestAddressList hypercall support")
b42967dcac1d ("x86/hyper-v: Fix indentation in hv_do_fast_hypercall16()")
3a025de64bf8 ("x86/hyperv: Enable PV qspinlock for Hyper-V")
eb914cfe72f4 ("X86/Hyper-V: Add flush HvFlushGuestPhysicalAddressSpace hypercall support")
...

On Thu, Jan 07, 2021 at 05:05:36AM +0000, Sunil Muthuswamy wrote:
> Currently, operations related to irq/msi in Hyper-V vPCI are

In comments in the patch, you use "IRQ" and "MSI". I don't know
whether "vPCI" means something or is a typo. I suppose it probably
means "virtual PCI" as below.

> x86-specific code. In order to support virtual PCI on Hyper-V for
> other architectures, introduce generic interfaces to replace the
> x86-specific ones. There are no functional changes in this patch.
>
> Signed-off-by: Sunil Muthuswamy <sunilmut@xxxxxxxxxxxxx>
> Signed-off-by: Boqun Feng (Microsoft) <boqun.feng@xxxxxxxxx>
> ...