extern int __init efi_reuse_config(u64 tables, int nr_tables);
extern void efi_delete_dummy_variable(void);
extern void efi_switch_mm(struct mm_struct *mm);
-extern void efi_recover_from_page_fault(unsigned long phys_addr);
+extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr);
extern void efi_free_boot_services(void);
/* kexec external ABI */
#include <linux/prefetch.h> /* prefetchw */
#include <linux/context_tracking.h> /* exception_enter(), ... */
#include <linux/uaccess.h> /* faulthandler_disabled() */
-#include <linux/efi.h> /* efi_recover_from_page_fault()*/
+#include <linux/efi.h> /* efi_crash_gracefully_on_page_fault()*/
#include <linux/mm_types.h>
#include <asm/cpufeature.h> /* boot_cpu_has, ... */
#include <asm/vsyscall.h> /* emulate_vsyscall */
#include <asm/vm86.h> /* struct vm86 */
#include <asm/mmu_context.h> /* vma_pkey() */
-#include <asm/efi.h> /* efi_recover_from_page_fault()*/
+#include <asm/efi.h> /* efi_crash_gracefully_on_page_fault()*/
#include <asm/desc.h> /* store_idt(), ... */
#include <asm/cpu_entry_area.h> /* exception stack */
#include <asm/pgtable_areas.h> /* VMALLOC_START, ... */
#endif
/*
- * Buggy firmware could access regions which might page fault, try to
- * recover from such faults.
+ * Buggy firmware could access regions which might page fault. If
+ * this happens, EFI has a special OOPS path that will try to
+ * avoid hanging the system.
*/
if (IS_ENABLED(CONFIG_EFI))
- efi_recover_from_page_fault(address);
+ efi_crash_gracefully_on_page_fault(address);
oops:
/*
* @return: Returns, if the page fault is not handled. This function
* will never return if the page fault is handled successfully.
*/
-void efi_recover_from_page_fault(unsigned long phys_addr)
+void efi_crash_gracefully_on_page_fault(unsigned long phys_addr)
{
if (!IS_ENABLED(CONFIG_X86_64))
return;
+ /*
+ * If we get an interrupt/NMI while processing an EFI runtime service
+ * then this is a regular OOPS, not an EFI failure.
+ */
+ if (in_interrupt())
+ return;
+
/*
* Make sure that an efi runtime service caused the page fault.
+ * READ_ONCE() because we might be OOPSing in a different thread,
+ * and we don't want to trip KTSAN while trying to OOPS.
*/
- if (efi_rts_work.efi_rts_id == EFI_NONE)
+ if (READ_ONCE(efi_rts_work.efi_rts_id) == EFI_NONE ||
+ current_work() != &efi_rts_work.work)
return;
/*
set_current_state(TASK_IDLE);
schedule();
}
-
- return;
}