Commit 58c80cc5 authored by H. Peter Anvin (Intel)'s avatar H. Peter Anvin (Intel) Committed by Borislav Petkov (AMD)
Browse files

x86/fred: Make exc_page_fault() work for FRED 



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: default avatarH. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: default avatarXin Li <xin3.li@intel.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Tested-by: default avatarShan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-22-xin3.li@intel.com
parent ad41a14c

arch/x86/mm/fault.c

+4 −1
Original line number Diff line number Diff line
@@ -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);