On 12/14/2023 2:20 AM, Sean Christopherson wrote:
On Wed, Dec 13, 2023, Dan1 Wu wrote:
On 12/12/2023 11:17 PM, Sean Christopherson wrote:
On Tue, Dec 12, 2023, Dan Wu wrote:
When running asyncpf test, it gets skipped without a clear reason:
./asyncpf
enabling apic
smp: waiting for 0 APs
paging enabled
cr0 = 80010011
cr3 = 107f000
cr4 = 20
install handler
enable async pf
alloc memory
start loop
end loop
start loop
end loop
SUMMARY: 0 tests
SKIP asyncpf (0 tests)
The reason is that KVM changed to use interrupt-based 'page-ready' notification
and abandoned #PF-based 'page-ready' notification mechanism. Interrupt-based
'page-ready' notification requires KVM_ASYNC_PF_DELIVERY_AS_INT to be set as well
in MSR_KVM_ASYNC_PF_EN to enable asyncpf.
This series tries to fix the problem by separating two testcases for different mechanisms.
- For old #PF-based notification, changes current asyncpf.c to add CPUID check
at the beginning. It checks (KVM_FEATURE_ASYNC_PF && !KVM_FEATURE_ASYNC_PF_INT),
otherwise it gets skipped.
- For new interrupt-based notification, add a new test, asyncpf-int.c, to check
(KVM_FEATURE_ASYNC_PF && KVM_FEATURE_ASYNC_PF_INT) and implement interrupt-based
'page-ready' handler.
Using #PF to deliver page-ready is completely dead, no? Unless I'm mistaken, let's
just drop the existing support and replace it with the interrupted-based mechanism.
I see no reason to continue maintaining the old crud. If someone wants to verify
an old, broken KVM, then they can use the old version of KUT.
Yes, since Linux v5.10 the feature asyncpf is deprecated.
So, just drop asyncpf.c and add asyncpf_int.c is enough, right?
I would rather not add asyncpf_int.c, and instead keep asyncpf.c and modify it to
use ASYNC_PF_INT. It _might_ be a bit more churn, but modifying the existing code
instead of dropping in a new file will better preserve the history, and may also
allow for finer grained patches (not sure on that one).
ok, I will modify it in the next version. Thanks for your review.
