Automatic merge of 'next-test' into merge-test (2026-08-03 18:39)

Author: maddy-kerneldev

arch/powerpc/include/asm/papr-watchdog.h

@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _ASM_POWERPC_PAPR_WATCHDOG_H
+#define _ASM_POWERPC_PAPR_WATCHDOG_H
+
+/*
+ * H_WATCHDOG Input
+ *
+ * R4: "flags":
+ *
+ *         Bits 48-55: "operation"
+ */
+#define PSERIES_WDTF_OP_START	0x100UL		/* start timer */
+#define PSERIES_WDTF_OP_STOP	0x200UL		/* stop timer */
+#define PSERIES_WDTF_OP_QUERY	0x300UL		/* query timer capabilities */
+
+/*
+ *         Bits 56-63: "timeoutAction" (for "Start Watchdog" only)
+ */
+#define PSERIES_WDTF_ACTION_HARD_POWEROFF	0x1UL	/* poweroff */
+#define PSERIES_WDTF_ACTION_HARD_RESTART	0x2UL	/* restart */
+#define PSERIES_WDTF_ACTION_DUMP_RESTART	0x3UL	/* dump + restart */
+
+/*
+ * R5: "watchdogNumber":
+ *       PAPR says use -1 (all ones) to stop all watchdogs.
+ */
+#define PSERIES_WDT_NUM_ALL	((unsigned long)-1)
+
+/*
+ * H_WATCHDOG Output
+ *
+ * R3: Return code
+ *
+ *     H_SUCCESS    The operation completed.
+ *
+ *     H_BUSY	    The hypervisor is too busy; retry the operation.
+ *
+ *     H_PARAMETER  The given "flags" are somehow invalid.  Either the
+ *                  "operation" or "timeoutAction" is invalid, or a
+ *                  reserved bit is set.
+ *
+ *     H_P2         The given "watchdogNumber" is zero or exceeds the
+ *                  supported maximum value.
+ *
+ *     H_P3         The given "timeoutInMs" is below the supported
+ *                  minimum value.
+ *
+ *     H_NOOP       The given "watchdogNumber" is already stopped.
+ *
+ *     H_HARDWARE   The operation failed for ineffable reasons.
+ *
+ *     H_FUNCTION   The H_WATCHDOG hypercall is not supported by this
+ *                  hypervisor.
+ *
+ * R4:
+ *
+ * - For the "Query Watchdog Capabilities" operation, a 64-bit
+ *   structure:
+ */
+#define PSERIES_WDTQ_MIN_TIMEOUT(cap)	(((cap) >> 48) & 0xffff)
+#define PSERIES_WDTQ_MAX_NUMBER(cap)	(((cap) >> 32) & 0xffff)
+
+#endif /* _ASM_POWERPC_PAPR_WATCHDOG_H */

arch/powerpc/include/asm/reg.h

@@ -1357,6 +1357,18 @@
 #define PVR_ARCH_31	0x0f000006
 #define PVR_ARCH_31_P11	0x0f000007
 
+/*
+ * Kernel-internal sentinel for invalid processor compatibility modes.
+ * PAPR specifies that the first byte of a valid logical PVR value is
+ * 0x0f. So 0xffffffff lies permanently outside the PAPR-defined range
+ * and is safe to repurpose. KVM stores it in vcpu->arch.arch_compat
+ * when userspace requests an unsupported compatibility mode (e.g.,
+ * Power11 PVR on a Power11 host booted in Power10 compat).
+ * kvmppc_sanity_check() detects this and prevents the vCPU from
+ * running with an unsupported arch_compat.
+ */
+#define PVR_ARCH_INVALID	0xffffffff
+
 /* Macros for setting and retrieving special purpose registers */
 #ifndef __ASSEMBLER__
 

arch/powerpc/include/asm/syscall.h

@@ -98,6 +98,12 @@ static inline void syscall_set_return_value(struct task_struct *task,
 			regs->gpr[3] = val;
 		}
 	}
+	/*
+	 * Mark that a return value has been explicitly set by seccomp or
+	 * ptrace so that system_call_exception() can skip the syscall
+	 * unconditionally, even when the user requested syscall(-1).
+	 */
+	set_thread_flag(TIF_SYSCALL_RET);
 }
 
 static inline void syscall_get_arguments(struct task_struct *task,

arch/powerpc/include/asm/thread_info.h

@@ -120,6 +120,7 @@ void arch_setup_new_exec(void);
 #endif
 #define TIF_POLLING_NRFLAG	19	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_32BIT		20	/* 32 bit binary */
+#define TIF_SYSCALL_RET		21	/* syscall error value set */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)

arch/powerpc/include/asm/xive.h

@@ -91,7 +91,7 @@ static inline bool xive_enabled(void) { return __xive_enabled; }
 
 bool xive_spapr_init(void);
 bool xive_native_init(void);
-void xive_smp_probe(void);
+int xive_smp_probe(void);
 int  xive_smp_prepare_cpu(unsigned int cpu);
 void xive_smp_setup_cpu(void);
 void xive_smp_disable_cpu(void);
@@ -153,7 +153,7 @@ static inline bool xive_enabled(void) { return false; }
 
 static inline bool xive_spapr_init(void) { return false; }
 static inline bool xive_native_init(void) { return false; }
-static inline void xive_smp_probe(void) { }
+static inline int xive_smp_probe(void) { return -EINVAL; }
 static inline int  xive_smp_prepare_cpu(unsigned int cpu) { return -EINVAL; }
 static inline void xive_smp_setup_cpu(void) { }
 static inline void xive_smp_disable_cpu(void) { }

arch/powerpc/kernel/head_64.S

@@ -713,14 +713,18 @@ p_end: .8byte _end - copy_to_here
 _GLOBAL(copy_and_flush)
 	addi	r5,r5,-8
 	addi	r6,r6,-8
-4:	li	r0,8			/* Use the smallest common	*/
-					/* denominator cache line	*/
-					/* size.  This results in	*/
-					/* extra cache line flushes	*/
-					/* but operation is correct.	*/
-					/* Can't get cache line size	*/
-					/* from NACA as it is being	*/
-					/* moved too.			*/
+4:	li	r0,8			/* r0 is the number of 8-byte words	*/
+					/* to copy per cache sync iteration.	*/
+					/* 8 words * 8 bytes = 64 bytes. 64B is	*/
+					/* the current default cache line size.	*/
+					/* This is a loop count, not a byte	*/
+					/* count. Increasing it may skip	*/
+					/* dcbst/icbi for lines in between and	*/
+					/* leave stale instructions in icache.	*/
+					/* This results in extra cache line	*/
+					/* flushes but operation is correct.	*/
+					/* Can't get cache line size from NACA	*/
+					/* as it is being moved too.		*/
 
 	mtctr	r0			/* put # words/line in ctr	*/
 3:	addi	r6,r6,8			/* copy a cache line		*/

arch/powerpc/kernel/irq.c

@@ -217,8 +217,12 @@ static __always_inline void call_do_softirq(const void *sp)
 		   [sp] "b" (sp), [offset] "i" (THREAD_SIZE - STACK_FRAME_MIN_SIZE),
 		   [callee] "i" (__do_softirq)
 		 : // Clobbers
-		   "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6",
-		   "cr7", "r0", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10",
+		   "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", "cr7", "r0",
+		  /* r2 may be clobbered by the callee when using PCREL mode in the ELFv2 ABI. */
+#ifdef CONFIG_PPC_KERNEL_PCREL
+		   "r2",
+#endif
+		   "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10",
 		   "r11", "r12"
 	);
 }
@@ -275,8 +279,12 @@ static __always_inline void call_do_irq(struct pt_regs *regs, void *sp)
 		   [sp] "b" (sp), [offset] "i" (THREAD_SIZE - STACK_FRAME_MIN_SIZE),
 		   [callee] "i" (__do_irq)
 		 : // Clobbers
-		   "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6",
-		   "cr7", "r0", "r4", "r5", "r6", "r7", "r8", "r9", "r10",
+		   "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", "cr7", "r0",
+		  /* r2 may be clobbered by the callee when using PCREL mode in the ELFv2 ABI. */
+#ifdef CONFIG_PPC_KERNEL_PCREL
+		   "r2",
+#endif
+		   "r4", "r5", "r6", "r7", "r8", "r9", "r10",
 		   "r11", "r12"
 	);
 }

arch/powerpc/kernel/smp.c

@@ -289,6 +289,9 @@ void smp_muxed_ipi_set_message(int cpu, int msg)
 
 void smp_muxed_ipi_message_pass(int cpu, int msg)
 {
+	if (!smp_ops->cause_ipi)
+		return;
+
 	smp_muxed_ipi_set_message(cpu, msg);
 
 	/*

arch/powerpc/kernel/syscall.c

@@ -22,6 +22,9 @@ notrace long system_call_exception(struct pt_regs *regs, unsigned long r0)
 	add_random_kstack_offset();
 	r0 = syscall_enter_from_user_mode(regs, r0);
 
+	if (unlikely(test_and_clear_thread_flag(TIF_SYSCALL_RET)))
+		return syscall_get_error(current, regs);
+
 	if (unlikely(r0 >= NR_syscalls)) {
 		if (unlikely(trap_is_unsupported_scv(regs))) {
 			/* Unsupported scv vector */

arch/powerpc/kvm/book3s_hv.c

@@ -446,7 +446,19 @@ static int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)
 			guest_pcr_bit = PCR_ARCH_300;
 			break;
 		case PVR_ARCH_31:
+			guest_pcr_bit = PCR_ARCH_31;
+			break;
 		case PVR_ARCH_31_P11:
+			/*
+			 * Need to check this for ISA 3.1, as Power10 and
+			 * Power11 share the same PCR. For any subsequent ISA
+			 * versions, this will be taken care of by the guest vs
+			 * host PCR comparison below.
+			 */
+			if (!cpu_has_feature(CPU_FTR_P11_PVR)) {
+				arch_compat = PVR_ARCH_INVALID;
+				goto out;
+			}
 			guest_pcr_bit = PCR_ARCH_31;
 			break;
 		default:
@@ -469,6 +481,7 @@ static int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)
 			return -EINVAL;
 	}
 
+out:
 	spin_lock(&vc->lock);
 	vc->arch_compat = arch_compat;
 	kvmhv_nestedv2_mark_dirty(vcpu, KVMPPC_GSID_LOGICAL_PVR);
@@ -479,7 +492,7 @@ static int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)
 	vc->pcr = (host_pcr_bit - guest_pcr_bit) | PCR_MASK;
 	spin_unlock(&vc->lock);
 
-	return 0;
+	return kvmppc_sanity_check(vcpu);
 }
 
 static void kvmppc_dump_regs(struct kvm_vcpu *vcpu)