[PATCH v2] KVM: selftests: Undef musl's PAGE_SIZE on x86 to avoid type differences

[PATCH v2] KVM: selftests: Undef musl's PAGE_SIZE on x86 to avoid type differences

[Sean Christopherson]

Before defining PAGE_SIZE in x86's processor.h, explicitly include the
system's limits.h and #undef PAGE_SIZE to workaround a conflict when using
musl where musl defines PAGE_SIZE as a signed 32-bit value, but KVM expects
it to be (and effectively requires it to be) an unsigned 64-bit value.

Reported-by: Aqib Faruqui <aqibaf@amazon.com>
Link: https://lore.kernel.org/kvm/aL8e0MMa4U2-nstQ@google.com
Cc: Hisam Mehboob <hisamshar@gmail.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---

v2:
 - Limit the hackery to KVM x86 selftests.
 - Ensure limits.h is included before PAGE_SIZE can get defined by processor.h

v1: https://lore.kernel.org/all/20260507234854.273536-2-hisamshar@gmail.com

 tools/testing/selftests/kvm/include/x86/processor.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/x86/processor.h b/tools/testing/selftests/kvm/include/x86/processor.h
index 5898a277a2e0..65fda03ea893 100644
--- a/tools/testing/selftests/kvm/include/x86/processor.h
+++ b/tools/testing/selftests/kvm/include/x86/processor.h
@@ -6,6 +6,14 @@
 #ifndef SELFTEST_KVM_PROCESSOR_H
 #define SELFTEST_KVM_PROCESSOR_H
 
+/*
+ * Explicitly include the system's limit.h and undefine PAGE_SIZE to workaround
+ * an incompatibility where musl defines PAGE_SIZE as a signed integer, whereas
+ * KVM selftests expect it to be a 64-bit unsigned value.
+ */
+#include <limits.h>
+#undef PAGE_SIZE
+
 #include <assert.h>
 #include <stdint.h>
 #include <syscall.h>

base-commit: cf7fa575900051e489f95944c65f432ea706ed73
-- 
2.56.0.542.g3ef89b7020-goog

Re: [PATCH v2] KVM: selftests: Undef musl's PAGE_SIZE on x86 to avoid type differences

[Sean Christopherson]

On Tue, 10 Nov 2026 10:24:51 -0800, Sean Christopherson wrote:
> Before defining PAGE_SIZE in x86's processor.h, explicitly include the
> system's limits.h and #undef PAGE_SIZE to workaround a conflict when using
> musl where musl defines PAGE_SIZE as a signed 32-bit value, but KVM expects
> it to be (and effectively requires it to be) an unsigned 64-bit value.

Applied to kvm-x86 selftests, thanks!

[1/1] KVM: selftests: Undef musl's PAGE_SIZE on x86 to avoid type differences
      https://github.com/kvm-x86/linux/commit/3efa3f8b6eb6

--
https://github.com/kvm-x86/linux/tree/next