Commit 9946f098 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'efi-fixes-for-v6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi 

Pull EFI fixes from Ard Biesheuvel:
 "Another couple of EFI fixes, of which the first two were already in
  -next when I sent out the previous PR, but they caused some issues on
  non-EFI boots so I let them simmer for a bit longer.

   - ensure the EFI ResetSystem and ACPI PRM calls are recognized as
     users of the EFI runtime, and therefore protected against
     exceptions

   - account for the EFI runtime stack in the stacktrace code

   - remove Matthew Garrett's MAINTAINERS entry for efivarfs"

* tag 'efi-fixes-for-v6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: Remove Matthew Garrett as efivarfs maintainer
  arm64: efi: Account for the EFI runtime stack in stack unwinder
  arm64: efi: Avoid workqueue to check whether EFI runtime is live
parents 2475bf02 e1fabbc8

MAINTAINERS

+0 −1
Original line number Diff line number Diff line
@@ -7615,7 +7615,6 @@ S: Maintained 
F:	drivers/firmware/efi/test/









EFI VARIABLE FILESYSTEM









M:	Matthew Garrett <matthew.garrett@nebula.com>









M:	Jeremy Kerr <jk@ozlabs.org>









M:	Ard Biesheuvel <ardb@kernel.org>









L:	linux-efi@vger.kernel.org
































arch/arm64/include/asm/efi.h



+9
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@@ -48,8 +48,17 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);







})



















extern spinlock_t efi_rt_lock;









extern u64 *efi_rt_stack_top;









efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...);



















/*









 * efi_rt_stack_top[-1] contains the value the stack pointer had before









 * switching to the EFI runtime stack.









 */









#define current_in_efi()						\









	(!preemptible() && efi_rt_stack_top != NULL &&			\









	 on_task_stack(current, READ_ONCE(efi_rt_stack_top[-1]), 1))



















#define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT)



















/*
































arch/arm64/include/asm/stacktrace.h



+15
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@@ -106,4 +106,19 @@ static inline struct stack_info stackinfo_get_sdei_critical(void)







#define stackinfo_get_sdei_critical()	stackinfo_get_unknown()









#endif



















#ifdef CONFIG_EFI









extern u64 *efi_rt_stack_top;



















static inline struct stack_info stackinfo_get_efi(void)









{









	unsigned long high = (u64)efi_rt_stack_top;









	unsigned long low = high - THREAD_SIZE;



















	return (struct stack_info) {









		.low = low,









		.high = high,









	};









}









#endif



















#endif	/* __ASM_STACKTRACE_H */
























arch/arm64/kernel/efi-rt-wrapper.S



+6
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@@ -46,7 +46,10 @@ SYM_FUNC_START(__efi_rt_asm_wrapper)







	mov	x4, x6









	blr	x8



















	mov	x16, sp









	mov	sp, x29









	str	xzr, [x16, #8]			// clear recorded task SP value



















	ldp	x1, x2, [sp, #16]









	cmp	x2, x18









	ldp	x29, x30, [sp], #112








@@ -71,6 +74,9 @@ SYM_FUNC_END(__efi_rt_asm_wrapper)







SYM_CODE_START(__efi_rt_asm_recover)









	mov	sp, x30



















	ldr_l	x16, efi_rt_stack_top		// clear recorded task SP value









	str	xzr, [x16, #-8]



















	ldp	x19, x20, [sp, #32]









	ldp	x21, x22, [sp, #48]









	ldp	x23, x24, [sp, #64]
































arch/arm64/kernel/efi.c



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−1






























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@@ -11,6 +11,7 @@







#include <linux/init.h>



















#include <asm/efi.h>









#include <asm/stacktrace.h>



















static bool region_is_misaligned(const efi_memory_desc_t *md)









{








@@ -154,7 +155,7 @@ asmlinkage efi_status_t __efi_rt_asm_recover(void);







bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg)









{









	 /* Check whether the exception occurred while running the firmware */









	if (current_work() != &efi_rts_work.work || regs->pc >= TASK_SIZE_64)









	if (!current_in_efi() || regs->pc >= TASK_SIZE_64)









		return false;



















	pr_err(FW_BUG "Unable to handle %s in EFI runtime service\n", msg);