Commit cef6c8c9 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux 

Pull arm64 fixes from Will Deacon:
 "Two important arm64 fixes ahead of the 6.16 release.

  The first fixes a regression introduced during the merge window where
  the KVM UUID (which is used to advertise KVM-specific hypercalls for
  things like time synchronisation in the guest) was corrupted thanks to
  an endianness bug introduced when converting the code to use the
  UUID_INIT() helper.

  The second fixes a stack-pointer corruption issue during
  context-switch which has been observed in the wild when taking a
  pseudo-NMI with shadow call stack enabled.

  Summary:

   - Fix broken UUID value for the KVM/arm64 hypervisor SMCCC interface

   - Fix stack corruption on context-switch, primarily seen on (but not
     limited to) configurations with both pNMI and SCS enabled"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64/entry: Mask DAIF in cpu_switch_to(), call_on_irq_stack()
  arm64: kvm, smccc: Fix vendor uuid
parents 407c114c d42e6c20

arch/arm64/include/asm/assembler.h

+5 −0
Original line number Diff line number Diff line
@@ -41,6 +41,11 @@ 
/*

 * Save/restore interrupts.

 */

	.macro save_and_disable_daif, flags

	mrs	\flags, daif

	msr	daifset, #0xf

	.endm



	.macro	save_and_disable_irq, flags

	mrs	\flags, daif

	msr	daifset, #3

arch/arm64/kernel/entry.S

+6 −0
Original line number Diff line number Diff line
@@ -825,6 +825,7 @@ SYM_CODE_END(__bp_harden_el1_vectors) 
 *

 */

SYM_FUNC_START(cpu_switch_to)

	save_and_disable_daif x11

	mov	x10, #THREAD_CPU_CONTEXT

	add	x8, x0, x10

	mov	x9, sp
@@ -848,6 +849,7 @@ SYM_FUNC_START(cpu_switch_to) 
	ptrauth_keys_install_kernel x1, x8, x9, x10

	scs_save x0

	scs_load_current

	restore_irq x11

	ret

SYM_FUNC_END(cpu_switch_to)

NOKPROBE(cpu_switch_to)
@@ -874,6 +876,7 @@ NOKPROBE(ret_from_fork) 
 * Calls func(regs) using this CPU's irq stack and shadow irq stack.

 */

SYM_FUNC_START(call_on_irq_stack)

	save_and_disable_daif x9

#ifdef CONFIG_SHADOW_CALL_STACK

	get_current_task x16

	scs_save x16
@@ -888,8 +891,10 @@ SYM_FUNC_START(call_on_irq_stack) 


	/* Move to the new stack and call the function there */

	add	sp, x16, #IRQ_STACK_SIZE

	restore_irq x9

	blr	x1



	save_and_disable_daif x9

	/*

	 * Restore the SP from the FP, and restore the FP and LR from the frame

	 * record.
@@ -897,6 +902,7 @@ SYM_FUNC_START(call_on_irq_stack) 
	mov	sp, x29

	ldp	x29, x30, [sp], #16

	scs_load_current

	restore_irq x9

	ret

SYM_FUNC_END(call_on_irq_stack)

NOKPROBE(call_on_irq_stack)

include/linux/arm-smccc.h

+1 −1
Original line number Diff line number Diff line
@@ -113,7 +113,7 @@ 


/* KVM UID value: 28b46fb6-2ec5-11e9-a9ca-4b564d003a74 */

#define ARM_SMCCC_VENDOR_HYP_UID_KVM UUID_INIT(\

	0xb66fb428, 0xc52e, 0xe911, \

	0x28b46fb6, 0x2ec5, 0x11e9, \

	0xa9, 0xca, 0x4b, 0x56, \

	0x4d, 0x00, 0x3a, 0x74)