KY Srinivasan <k...@microsoft.com> writes: >> -----Original Message----- >> From: Michael Kelley (EOSG) >> Sent: Tuesday, June 19, 2018 10:57 AM >> To: Vitaly Kuznetsov <vkuzn...@redhat.com>; x...@kernel.org >> Cc: de...@linuxdriverproject.org; linux-ker...@vger.kernel.org; KY >> Srinivasan <k...@microsoft.com>; Haiyang Zhang >> <haiya...@microsoft.com>; Stephen Hemminger >> <sthem...@microsoft.com>; Thomas Gleixner <t...@linutronix.de>; Ingo >> Molnar <mi...@redhat.com>; H. Peter Anvin <h...@zytor.com>; Tianyu Lan >> <tianyu....@microsoft.com> >> Subject: RE: [PATCH] x86/hyper-v: use cheaper >> HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE} hypercalls when possible >> >> ... >>> >> This is a good idea. We should probably do the same with the hypercalls for >> sending >> IPIs -- try the simpler version first and move to the more complex _EX >> version only >> if necessary. > I am not sure if this would work correctly. When I was developing the IPI > enlightenment, > what I remember was that the guest is expected to use the API recommended by > the Hypervisor. >
I was under the same impression when I implemented PV TLB flush. Turns out HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED is a misnomer or at least Windows treats it as HV_X64_EX_PROCESSOR_MASKS_AVAILABLE instead using only when needed. My guess would be that the situation with IPI is the same. In any case I can try to implement Hyper-V style PV IPIs for Windows in KVM and we'll see how Windows uses these hypercalls :-) -- Vitaly _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel