Re: [PATCH v2 1/2] x86/vlapic: Fix handling of writes to APIC_ESR

2025-03-06 Thread Andrew Cooper
On 05/03/2025 1:49 pm, Jan Beulich wrote: > On 03.03.2025 19:53, Andrew Cooper wrote: >> Xen currently presents APIC_ESR to guests as a simple read/write register. >> >> This is incorrect. The SDM states: >> >> The ESR is a write/read register. Before attempt to read from the ESR, >> software

Re: [PATCH v2 1/2] x86/vlapic: Fix handling of writes to APIC_ESR

2025-03-05 Thread Jan Beulich
On 03.03.2025 19:53, Andrew Cooper wrote: > Xen currently presents APIC_ESR to guests as a simple read/write register. > > This is incorrect. The SDM states: > > The ESR is a write/read register. Before attempt to read from the ESR, > software should first write to it. (The value written doe

[PATCH v2 1/2] x86/vlapic: Fix handling of writes to APIC_ESR

2025-03-03 Thread Andrew Cooper
Xen currently presents APIC_ESR to guests as a simple read/write register. This is incorrect. The SDM states: The ESR is a write/read register. Before attempt to read from the ESR, software should first write to it. (The value written does not affect the values read subsequently; only zero