Merge branch 'for-next/misc' into for-next/core

* for-next/misc:
  arm64/sysreg: refactor deprecated strncpy
  arm64: sysreg: Generate C compiler warnings on {read,write}_sysreg_s arguments
  arm64: sdei: abort running SDEI handlers during crash
  arm64: Explicitly include correct DT includes
  arm64/Kconfig: Sort the RCpc feature under the ARMv8.3 features menu
  arm64: vdso: remove two .altinstructions related symbols
  arm64/ptrace: Clean up error handling path in sve_set_common()

arch/arm64/Kconfig

@@ -1793,9 +1793,6 @@ config ARM64_PAN
 	  The feature is detected at runtime, and will remain as a 'nop'
 	  instruction if the cpu does not implement the feature.
 
-config AS_HAS_LDAPR
-	def_bool $(as-instr,.arch_extension rcpc)
-
 config AS_HAS_LSE_ATOMICS
 	def_bool $(as-instr,.arch_extension lse)
 
@@ -1933,6 +1930,9 @@ config AS_HAS_ARMV8_3
 config AS_HAS_CFI_NEGATE_RA_STATE
 	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
 
+config AS_HAS_LDAPR
+	def_bool $(as-instr,.arch_extension rcpc)
+
 endmenu # "ARMv8.3 architectural features"
 
 menu "ARMv8.4 architectural features"

arch/arm64/include/asm/sdei.h

@@ -17,6 +17,9 @@
 
 #include <asm/virt.h>
 
+DECLARE_PER_CPU(struct sdei_registered_event *, sdei_active_normal_event);
+DECLARE_PER_CPU(struct sdei_registered_event *, sdei_active_critical_event);
+
 extern unsigned long sdei_exit_mode;
 
 /* Software Delegated Exception entry point from firmware*/
@@ -29,6 +32,9 @@ asmlinkage void __sdei_asm_entry_trampoline(unsigned long event_num,
 						   unsigned long pc,
 						   unsigned long pstate);
 
+/* Abort a running handler. Context is discarded. */
+void __sdei_handler_abort(void);
+
 /*
  * The above entry point does the minimum to call C code. This function does
  * anything else, before calling the driver.

arch/arm64/include/asm/sysreg.h

@@ -803,15 +803,21 @@
 /*
  * For registers without architectural names, or simply unsupported by
  * GAS.
+ *
+ * __check_r forces warnings to be generated by the compiler when
+ * evaluating r which wouldn't normally happen due to being passed to
+ * the assembler via __stringify(r).
  */
 #define read_sysreg_s(r) ({						\
 	u64 __val;							\
+	u32 __maybe_unused __check_r = (u32)(r);			\
 	asm volatile(__mrs_s("%0", r) : "=r" (__val));			\
 	__val;								\
 })
 
 #define write_sysreg_s(v, r) do {					\
 	u64 __val = (u64)(v);						\
+	u32 __maybe_unused __check_r = (u32)(r);			\
 	asm volatile(__msr_s(r, "%x0") : : "rZ" (__val));		\
 } while (0)
 

arch/arm64/kernel/cpuidle.c

@@ -9,8 +9,6 @@
 #include <linux/acpi.h>
 #include <linux/cpuidle.h>
 #include <linux/cpu_pm.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
 #include <linux/psci.h>
 
 #ifdef CONFIG_ACPI_PROCESSOR_IDLE

arch/arm64/kernel/entry.S

@@ -986,9 +986,13 @@ SYM_CODE_START(__sdei_asm_handler)
 
 	mov	x19, x1
 
-#if defined(CONFIG_VMAP_STACK) || defined(CONFIG_SHADOW_CALL_STACK)
+	/* Store the registered-event for crash_smp_send_stop() */
 	ldrb	w4, [x19, #SDEI_EVENT_PRIORITY]
-#endif
+	cbnz	w4, 1f
+	adr_this_cpu dst=x5, sym=sdei_active_normal_event, tmp=x6
+	b	2f
+1:	adr_this_cpu dst=x5, sym=sdei_active_critical_event, tmp=x6
+2:	str	x19, [x5]
 
 #ifdef CONFIG_VMAP_STACK
 	/*
@@ -1055,6 +1059,14 @@ SYM_CODE_START(__sdei_asm_handler)
 
 	ldr_l	x2, sdei_exit_mode
 
+	/* Clear the registered-event seen by crash_smp_send_stop() */
+	ldrb	w3, [x4, #SDEI_EVENT_PRIORITY]
+	cbnz	w3, 1f
+	adr_this_cpu dst=x5, sym=sdei_active_normal_event, tmp=x6
+	b	2f
+1:	adr_this_cpu dst=x5, sym=sdei_active_critical_event, tmp=x6
+2:	str	xzr, [x5]
+
 alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0
 	sdei_handler_exit exit_mode=x2
 alternative_else_nop_endif
@@ -1065,4 +1077,15 @@ alternative_else_nop_endif
 #endif
 SYM_CODE_END(__sdei_asm_handler)
 NOKPROBE(__sdei_asm_handler)
+
+SYM_CODE_START(__sdei_handler_abort)
+	mov_q	x0, SDEI_1_0_FN_SDEI_EVENT_COMPLETE_AND_RESUME
+	adr	x1, 1f
+	ldr_l	x2, sdei_exit_mode
+	sdei_handler_exit exit_mode=x2
+	// exit the handler and jump to the next instruction.
+	// Exit will stomp x0-x17, PSTATE, ELR_ELx, and SPSR_ELx.
+1:	ret
+SYM_CODE_END(__sdei_handler_abort)
+NOKPROBE(__sdei_handler_abort)
 #endif /* CONFIG_ARM_SDE_INTERFACE */

arch/arm64/kernel/idreg-override.c

@@ -262,9 +262,9 @@ static __init void __parse_cmdline(const char *cmdline, bool parse_aliases)
 		if (!len)
 			return;
 
-		len = min(len, ARRAY_SIZE(buf) - 1);
-		strncpy(buf, cmdline, len);
-		buf[len] = 0;
+		len = strscpy(buf, cmdline, ARRAY_SIZE(buf));
+		if (len == -E2BIG)
+			len = ARRAY_SIZE(buf) - 1;
 
 		if (strcmp(buf, "--") == 0)
 			return;

arch/arm64/kernel/pci.c

@@ -11,8 +11,6 @@
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
-#include <linux/of_pci.h>
-#include <linux/of_platform.h>
 #include <linux/pci.h>
 #include <linux/pci-acpi.h>
 #include <linux/pci-ecam.h>

arch/arm64/kernel/ptrace.c

@@ -884,7 +884,8 @@ static int sve_set_common(struct task_struct *target,
 			break;
 		default:
 			WARN_ON_ONCE(1);
-			return -EINVAL;
+			ret = -EINVAL;
+			goto out;
 		}
 
 		/*

arch/arm64/kernel/sdei.c

@@ -47,6 +47,9 @@ DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr);
 DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr);
 #endif
 
+DEFINE_PER_CPU(struct sdei_registered_event *, sdei_active_normal_event);
+DEFINE_PER_CPU(struct sdei_registered_event *, sdei_active_critical_event);
+
 static void _free_sdei_stack(unsigned long * __percpu *ptr, int cpu)
 {
 	unsigned long *p;

arch/arm64/kernel/smp.c

@@ -1044,10 +1044,8 @@ void crash_smp_send_stop(void)
 	 * If this cpu is the only one alive at this point in time, online or
 	 * not, there are no stop messages to be sent around, so just back out.
 	 */
-	if (num_other_online_cpus() == 0) {
-		sdei_mask_local_cpu();
-		return;
-	}
+	if (num_other_online_cpus() == 0)
+		goto skip_ipi;
 
 	cpumask_copy(&mask, cpu_online_mask);
 	cpumask_clear_cpu(smp_processor_id(), &mask);
@@ -1066,7 +1064,9 @@ void crash_smp_send_stop(void)
 		pr_warn("SMP: failed to stop secondary CPUs %*pbl\n",
 			cpumask_pr_args(&mask));
 
+skip_ipi:
 	sdei_mask_local_cpu();
+	sdei_handler_abort();
 }
 
 bool smp_crash_stop_failed(void)

arch/arm64/kernel/vdso/vdso.lds.S

@@ -50,9 +50,7 @@ SECTIONS
 
 	. = ALIGN(4);
 	.altinstructions : {
-		__alt_instructions = .;
 		*(.altinstructions)
-		__alt_instructions_end = .;
 	}
 
 	.dynamic	: { *(.dynamic) }		:text	:dynamic

drivers/firmware/arm_sdei.c

@@ -1095,3 +1095,22 @@ int sdei_event_handler(struct pt_regs *regs,
 	return err;
 }
 NOKPROBE_SYMBOL(sdei_event_handler);
+
+void sdei_handler_abort(void)
+{
+	/*
+	 * If the crash happened in an SDEI event handler then we need to
+	 * finish the handler with the firmware so that we can have working
+	 * interrupts in the crash kernel.
+	 */
+	if (__this_cpu_read(sdei_active_critical_event)) {
+	        pr_warn("still in SDEI critical event context, attempting to finish handler.\n");
+	        __sdei_handler_abort();
+	        __this_cpu_write(sdei_active_critical_event, NULL);
+	}
+	if (__this_cpu_read(sdei_active_normal_event)) {
+	        pr_warn("still in SDEI normal event context, attempting to finish handler.\n");
+	        __sdei_handler_abort();
+	        __this_cpu_write(sdei_active_normal_event, NULL);
+	}
+}

include/linux/arm_sdei.h

@@ -47,10 +47,12 @@ int sdei_unregister_ghes(struct ghes *ghes);
 int sdei_mask_local_cpu(void);
 int sdei_unmask_local_cpu(void);
 void __init sdei_init(void);
+void sdei_handler_abort(void);
 #else
 static inline int sdei_mask_local_cpu(void) { return 0; }
 static inline int sdei_unmask_local_cpu(void) { return 0; }
 static inline void sdei_init(void) { }
+static inline void sdei_handler_abort(void) { }
 #endif /* CONFIG_ARM_SDE_INTERFACE */