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x86/fred: Make exc_page_fault() work for FRED

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On a FRED system, the faulting address (CR2) is passed on the stack,
to avoid the problem of transient state.  Thus the page fault address
is read from the FRED stack frame instead of CR2 when FRED is enabled.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Shan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-22-xin3.li@intel.com
This commit is contained in:
H. Peter Anvin (Intel) 2023-12-05 02:50:10 -08:00 committed by Borislav Petkov (AMD)
parent ad41a14cc2
commit 58c80cc55e
1 changed files with 4 additions and 1 deletions
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5
arch/x86/mm/fault.c
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@ -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/fred.h>
#define CREATE_TRACE_POINTS
#include <asm/trace/exceptions.h>
@ -1518,8 +1519,10 @@ handle_page_fault(struct pt_regs *regs, unsigned long error_code,
DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault)
{
unsigned long address = read_cr2();
irqentry_state_t state;
unsigned long address;
address = cpu_feature_enabled(X86_FEATURE_FRED) ? fred_event_data(regs) : read_cr2();
prefetchw(&current->mm->mmap_lock);