| Message ID | 20250215012032.1206409-4-seanjc@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | x86: Bump per-CPU stack/data to 12KiB | expand |
diff --git a/lib/x86/apic-defs.h b/lib/x86/apic-defs.h index fde1db38..5a1dff3a 100644 --- a/lib/x86/apic-defs.h +++ b/lib/x86/apic-defs.h @@ -3,10 +3,11 @@ /* * Abuse this header file to hold the number of max-cpus and the size of the - * per-CPU stack/data area, making them available both in C and ASM. + * per-CPU stack/data area, making them available both in C and ASM. One page + * for per-CPU, and two pages for the stack (plus some buffer in-between). */ #define MAX_TEST_CPUS (255) -#define PER_CPU_SIZE (4096) +#define PER_CPU_SIZE (3 * 4096) /* * Constants for various Intel APICs. (local APIC, IOAPIC, etc.)
Increase the size of the per-CPU stack/data area from one page to three, i.e. from 4KiB to 12KiB. KVM-Unit-Tests currently places the per-CPU data at the bottom of the stack page, i.e. the stack "page" is actually a page minus the size of the per-CPU area. And of course there's no guard page or buffer in between the two, and so overflowing the stack clobbers per-CPU data and sends tests into the weeds in weird ways. Punt on less awful infrastructure, and settle for fixing the most egregious problem of tests having less than 4KiB of stack to work with. Signed-off-by: Sean Christopherson <seanjc@google.com> --- lib/x86/apic-defs.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)