2023-10-16 13:29:40

by Michael Roth

[permalink] [raw]
Subject: [PATCH v10 10/50] x86/fault: Report RMP page faults for kernel addresses

RMP #PFs on kernel addresses are fatal and should never happen in
practice. They indicate a bug in the host kernel somewhere, so dump some
information about any RMP entries related to the faulting address to aid
with debugging.

Signed-off-by: Michael Roth <[email protected]>
---
arch/x86/mm/fault.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 7858b9515d4a..9f154beef9c7 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -34,6 +34,7 @@
#include <asm/kvm_para.h> /* kvm_handle_async_pf */
#include <asm/vdso.h> /* fixup_vdso_exception() */
#include <asm/irq_stack.h>
+#include <asm/sev-host.h> /* sev_dump_rmpentry() */

#define CREATE_TRACE_POINTS
#include <asm/trace/exceptions.h>
@@ -580,6 +581,9 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad
}

dump_pagetable(address);
+
+ if (error_code & X86_PF_RMP)
+ sev_dump_hva_rmpentry(address);
}

static noinline void
--
2.25.1