From: guenther <guenther@openbsd.org>
Date: Sun, 7 Aug 2022 23:56:06 +0000 (+0000)
Subject: Start to add annotations to the cpu_info members, doing I/a/o for
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=0403d5bcc6af6e3b8d03ad1c6de319d5acc58295;p=openbsd

Start to add annotations to the cpu_info members, doing I/a/o for
immutable/atomic/owned ala <sys/proc.h>.  Move CPUF_USERSEGS and
CPUF_USERXSTATE, which really are private to the CPU, into a new
ci_pflags and rename s/CPUF_/CPUPF_/.  Make all (remaining) ci_flags
alterations via atomic_{set,clear}bits_int(), so its annotation
isn't a lie.  Delete ci_info member as unused all the way from
rev 1.1

ok jsg@ mlarkin@
---

diff --git a/sys/arch/amd64/amd64/acpi_machdep.c b/sys/arch/amd64/amd64/acpi_machdep.c
index 373466415dd..db68939ed1e 100644
--- a/sys/arch/amd64/amd64/acpi_machdep.c
+++ b/sys/arch/amd64/amd64/acpi_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: acpi_machdep.c,v 1.103 2022/02/21 11:03:39 mpi Exp $	*/
+/*	$OpenBSD: acpi_machdep.c,v 1.104 2022/08/07 23:56:06 guenther Exp $	*/
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  *
@@ -406,7 +406,7 @@ acpi_sleep_cpu(struct acpi_softc *sc, int state)
 	 */
 	if (acpi_savecpu()) {
 		/* Suspend path */
-		KASSERT((curcpu()->ci_flags & CPUF_USERXSTATE) == 0);
+		KASSERT((curcpu()->ci_pflags & CPUPF_USERXSTATE) == 0);
 		wbinvd();
 
 #ifdef HIBERNATE
@@ -547,7 +547,7 @@ resume_mp(void)
 		ci->ci_idepth = 0;
 		ci->ci_handled_intr_level = IPL_NONE;
 
-		ci->ci_flags &= ~CPUF_PRESENT;
+		atomic_clearbits_int(&ci->ci_flags, CPUF_PRESENT);
 		cpu_start_secondary(ci);
 	}
 	cpu_boot_secondary_processors();
diff --git a/sys/arch/amd64/amd64/cpu.c b/sys/arch/amd64/amd64/cpu.c
index 4778347a12e..413938981b6 100644
--- a/sys/arch/amd64/amd64/cpu.c
+++ b/sys/arch/amd64/amd64/cpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.c,v 1.156 2022/04/26 08:35:30 claudio Exp $	*/
+/*	$OpenBSD: cpu.c,v 1.157 2022/08/07 23:56:06 guenther Exp $	*/
 /* $NetBSD: cpu.c,v 1.1 2003/04/26 18:39:26 fvdl Exp $ */
 
 /*-
@@ -593,7 +593,8 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	switch (caa->cpu_role) {
 	case CPU_ROLE_SP:
 		printf("(uniprocessor)\n");
-		ci->ci_flags |= CPUF_PRESENT | CPUF_SP | CPUF_PRIMARY;
+		atomic_setbits_int(&ci->ci_flags,
+		    CPUF_PRESENT | CPUF_SP | CPUF_PRIMARY);
 		cpu_intr_init(ci);
 #ifndef SMALL_KERNEL
 		cpu_ucode_apply(ci);
@@ -610,7 +611,8 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 
 	case CPU_ROLE_BP:
 		printf("apid %d (boot processor)\n", caa->cpu_apicid);
-		ci->ci_flags |= CPUF_PRESENT | CPUF_BSP | CPUF_PRIMARY;
+		atomic_setbits_int(&ci->ci_flags,
+		    CPUF_PRESENT | CPUF_BSP | CPUF_PRIMARY);
 		cpu_intr_init(ci);
 		identifycpu(ci);
 #ifdef MTRR
@@ -762,7 +764,7 @@ cpu_init(struct cpu_info *ci)
 #endif /* NVMM > 0 */
 
 #ifdef MULTIPROCESSOR
-	ci->ci_flags |= CPUF_RUNNING;
+	atomic_setbits_int(&ci->ci_flags, CPUF_RUNNING);
 	/*
 	 * Big hammer: flush all TLB entries, including ones from PTEs
 	 * with the G bit set.  This should only be necessary if TLB
@@ -833,7 +835,7 @@ cpu_start_secondary(struct cpu_info *ci)
 	int i;
 	u_long s;
 
-	ci->ci_flags |= CPUF_AP;
+	atomic_setbits_int(&ci->ci_flags, CPUF_AP);
 
 	pmap_kenter_pa(MP_TRAMPOLINE, MP_TRAMPOLINE, PROT_READ | PROT_EXEC);
 	pmap_kenter_pa(MP_TRAMP_DATA, MP_TRAMP_DATA, PROT_READ | PROT_WRITE);
@@ -946,7 +948,7 @@ cpu_hatch(void *v)
 	 * off at this point.
 	 */
 	wbinvd();
-	ci->ci_flags |= CPUF_PRESENT;
+	atomic_setbits_int(&ci->ci_flags, CPUF_PRESENT);
 	ci->ci_tsc_skew = 0;	/* reset on resume */
 	tsc_sync_ap(ci);
 
diff --git a/sys/arch/amd64/amd64/fpu.c b/sys/arch/amd64/amd64/fpu.c
index 1fc1e5f5cac..438de255bd6 100644
--- a/sys/arch/amd64/amd64/fpu.c
+++ b/sys/arch/amd64/amd64/fpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fpu.c,v 1.42 2020/11/30 02:56:42 jsg Exp $	*/
+/*	$OpenBSD: fpu.c,v 1.43 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: fpu.c,v 1.1 2003/04/26 18:39:28 fvdl Exp $	*/
 
 /*-
@@ -99,8 +99,8 @@ fputrap(int type)
 	u_int32_t mxcsr, statbits;
 	u_int16_t cw;
 
-	KASSERT(ci->ci_flags & CPUF_USERXSTATE);
-	ci->ci_flags &= ~CPUF_USERXSTATE;
+	KASSERT(ci->ci_pflags & CPUPF_USERXSTATE);
+	ci->ci_pflags &= ~CPUPF_USERXSTATE;
 	fpusavereset(sfp);
 
 	if (type == T_XMM) {
@@ -149,8 +149,8 @@ fpu_kernel_enter(void)
 	struct cpu_info *ci = curcpu();
 
 	/* save curproc's FPU state if we haven't already */
-	if (ci->ci_flags & CPUF_USERXSTATE) {
-		ci->ci_flags &= ~CPUF_USERXSTATE;
+	if (ci->ci_pflags & CPUPF_USERXSTATE) {
+		ci->ci_pflags &= ~CPUPF_USERXSTATE;
 		fpusavereset(&curproc->p_addr->u_pcb.pcb_savefpu);
 	} else {
 		fpureset();
diff --git a/sys/arch/amd64/amd64/genassym.cf b/sys/arch/amd64/amd64/genassym.cf
index 0db65e55cb6..c9e4ced195c 100644
--- a/sys/arch/amd64/amd64/genassym.cf
+++ b/sys/arch/amd64/amd64/genassym.cf
@@ -1,4 +1,4 @@
-#	$OpenBSD: genassym.cf,v 1.42 2021/06/18 06:17:28 guenther Exp $
+#	$OpenBSD: genassym.cf,v 1.43 2022/08/07 23:56:06 guenther Exp $
 #	Written by Artur Grabowski art@openbsd.org, Public Domain
 
 include <sys/param.h>
@@ -120,7 +120,7 @@ member	CPU_INFO_MUTEX_LEVEL	ci_mutex_level
 endif
 member	CPU_INFO_GDT		ci_gdt
 member	CPU_INFO_TSS		ci_tss
-member	CPU_INFO_FLAGS		ci_flags
+member	CPU_INFO_PFLAGS		ci_pflags
 member	CPU_INFO_KERN_CR3	ci_kern_cr3
 member	CPU_INFO_USER_CR3	ci_user_cr3
 member	CPU_INFO_KERN_RSP	ci_kern_rsp
@@ -128,8 +128,8 @@ member	CPU_INFO_INTR_RSP	ci_intr_rsp
 member	CPU_INFO_MDS_BUF	ci_mds_buf
 member	CPU_INFO_MDS_TMP	ci_mds_tmp
 
-export	CPUF_USERSEGS
-export	CPUF_USERXSTATE
+export	CPUPF_USERSEGS
+export	CPUPF_USERXSTATE
 
 struct	intrsource
 member	is_recurse
diff --git a/sys/arch/amd64/amd64/identcpu.c b/sys/arch/amd64/amd64/identcpu.c
index e633f932a65..e1748de7bc1 100644
--- a/sys/arch/amd64/amd64/identcpu.c
+++ b/sys/arch/amd64/amd64/identcpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: identcpu.c,v 1.125 2022/07/12 04:46:00 jsg Exp $	*/
+/*	$OpenBSD: identcpu.c,v 1.126 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: identcpu.c,v 1.1 2003/04/26 18:39:28 fvdl Exp $	*/
 
 /*
@@ -580,25 +580,23 @@ identifycpu(struct cpu_info *ci)
 		if (!strcmp(cpu_vendor, "GenuineIntel")) {
 			if ((ci->ci_family == 0x0f && ci->ci_model >= 0x03) ||
 			    (ci->ci_family == 0x06 && ci->ci_model >= 0x0e)) {
-				ci->ci_flags |= CPUF_CONST_TSC;
+				atomic_setbits_int(&ci->ci_flags, CPUF_CONST_TSC);
 			}
 		} else if (!strcmp(cpu_vendor, "CentaurHauls")) {
 			/* VIA */
 			if (ci->ci_model >= 0x0f) {
-				ci->ci_flags |= CPUF_CONST_TSC;
+				atomic_setbits_int(&ci->ci_flags, CPUF_CONST_TSC);
 			}
 		} else if (!strcmp(cpu_vendor, "AuthenticAMD")) {
 			if (cpu_apmi_edx & CPUIDEDX_ITSC) {
-				/* Invariant TSC indicates constant TSC on
-				 * AMD.
-				 */
-				ci->ci_flags |= CPUF_CONST_TSC;
+				/* Invariant TSC indicates constant TSC on AMD */
+				atomic_setbits_int(&ci->ci_flags, CPUF_CONST_TSC);
 			}
 		}
 
 		/* Check if it's an invariant TSC */
 		if (cpu_apmi_edx & CPUIDEDX_ITSC)
-			ci->ci_flags |= CPUF_INVAR_TSC;
+			atomic_setbits_int(&ci->ci_flags, CPUF_INVAR_TSC);
 
 		tsc_identify(ci);
 	}
diff --git a/sys/arch/amd64/amd64/ipifuncs.c b/sys/arch/amd64/amd64/ipifuncs.c
index b04e15e3912..277d727c75f 100644
--- a/sys/arch/amd64/amd64/ipifuncs.c
+++ b/sys/arch/amd64/amd64/ipifuncs.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipifuncs.c,v 1.36 2021/08/31 17:40:59 dv Exp $	*/
+/*	$OpenBSD: ipifuncs.c,v 1.37 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: ipifuncs.c,v 1.1 2003/04/26 18:39:28 fvdl Exp $ */
 
 /*-
@@ -124,7 +124,7 @@ x86_64_ipi_halt(struct cpu_info *ci)
 	intr_disable();
 	lapic_disable();
 	wbinvd();
-	ci->ci_flags &= ~CPUF_RUNNING;
+	atomic_clearbits_int(&ci->ci_flags, CPUF_RUNNING);
 	wbinvd();
 
 	for(;;) {
diff --git a/sys/arch/amd64/amd64/locore.S b/sys/arch/amd64/amd64/locore.S
index ef5c27256ee..2944720cc40 100644
--- a/sys/arch/amd64/amd64/locore.S
+++ b/sys/arch/amd64/amd64/locore.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.S,v 1.127 2021/12/31 10:40:30 jsg Exp $	*/
+/*	$OpenBSD: locore.S,v 1.128 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: locore.S,v 1.13 2004/03/25 18:33:17 drochner Exp $	*/
 
 /*
@@ -374,7 +374,7 @@ ENTRY(cpu_switchto)
 	 * If the old proc ran in userspace then save the
 	 * floating-point/"extended state" registers
 	 */
-	testl	$CPUF_USERXSTATE,CPUVAR(FLAGS)
+	testl	$CPUPF_USERXSTATE,CPUVAR(PFLAGS)
 	jz	.Lxstate_reset
 
 	movq	%r13, %rdi
@@ -394,16 +394,16 @@ switch_exited:
 	CODEPATCH_START
 	fxrstor64	(%rdi)
 	CODEPATCH_END(CPTAG_XRSTOR)
-	andl	$~CPUF_USERXSTATE,CPUVAR(FLAGS)
+	andl	$~CPUPF_USERXSTATE,CPUVAR(PFLAGS)
 
 .Lxstate_reset:
 	/*
 	 * If the segment registers haven't been reset since the old proc
 	 * ran in userspace then reset them now
 	 */
-	testl	$CPUF_USERSEGS,CPUVAR(FLAGS)
+	testl	$CPUPF_USERSEGS,CPUVAR(PFLAGS)
 	jz	restore_saved
-	andl	$~CPUF_USERSEGS,CPUVAR(FLAGS)
+	andl	$~CPUPF_USERSEGS,CPUVAR(PFLAGS)
 
 	/* set %ds, %es, %fs, and %gs to expected value to prevent info leak */
 	movw	$(GSEL(GUDATA_SEL, SEL_UPL)),%ax
@@ -642,11 +642,11 @@ IDTVEC_NOALIGN(syscall)
 	jne	intr_user_exit_post_ast
 
 	/* Restore FPU/"extended CPU state" if it's not already in the CPU */
-	testl	$CPUF_USERXSTATE,CPUVAR(FLAGS)
+	testl	$CPUPF_USERXSTATE,CPUVAR(PFLAGS)
 	jz	.Lsyscall_restore_xstate
 
 	/* Restore FS.base if it's not already in the CPU */
-	testl	$CPUF_USERSEGS,CPUVAR(FLAGS)
+	testl	$CPUPF_USERSEGS,CPUVAR(PFLAGS)
 	jz	.Lsyscall_restore_fsbase
 
 .Lsyscall_restore_registers:
@@ -712,13 +712,13 @@ KUTEXT_PAGE_END
 	_ALIGN_TRAPS
 	/* in this case, need FS.base but not xstate, rarely happens */
 .Lsyscall_restore_fsbase:	/* CPU doesn't have curproc's FS.base */
-	orl	$CPUF_USERSEGS,CPUVAR(FLAGS)
+	orl	$CPUPF_USERSEGS,CPUVAR(PFLAGS)
 	movq	CPUVAR(CURPCB),%rdi
 	jmp	.Lsyscall_restore_fsbase_real
 
 	_ALIGN_TRAPS
 .Lsyscall_restore_xstate:	/* CPU doesn't have curproc's xstate */
-	orl	$(CPUF_USERXSTATE|CPUF_USERSEGS),CPUVAR(FLAGS)
+	orl	$(CPUPF_USERXSTATE|CPUPF_USERSEGS),CPUVAR(PFLAGS)
 	movq	CPUVAR(CURPCB),%rdi
 	movq	xsave_mask(%rip),%rdx
 	movl	%edx,%eax
@@ -812,7 +812,7 @@ GENTRY(intr_user_exit)
 
 intr_user_exit_post_ast:
 	/* Restore FPU/"extended CPU state" if it's not already in the CPU */
-	testl	$CPUF_USERXSTATE,CPUVAR(FLAGS)
+	testl	$CPUPF_USERXSTATE,CPUVAR(PFLAGS)
 	jz	.Lintr_restore_xstate
 
 #ifdef DIAGNOSTIC
@@ -822,7 +822,7 @@ intr_user_exit_post_ast:
 #endif /* DIAGNOSTIC */
 
 	/* Restore FS.base if it's not already in the CPU */
-	testl	$CPUF_USERSEGS,CPUVAR(FLAGS)
+	testl	$CPUPF_USERSEGS,CPUVAR(PFLAGS)
 	jz	.Lintr_restore_fsbase
 
 .Lintr_restore_registers:
@@ -911,7 +911,7 @@ KTEXT_PAGE_END
 	.text
 	_ALIGN_TRAPS
 .Lintr_restore_xstate:		/* CPU doesn't have curproc's xstate */
-	orl	$CPUF_USERXSTATE,CPUVAR(FLAGS)
+	orl	$CPUPF_USERXSTATE,CPUVAR(PFLAGS)
 	movq	CPUVAR(CURPCB),%rdi
 #if PCB_SAVEFPU != 0
 	addq	$PCB_SAVEFPU,%rdi
@@ -921,7 +921,7 @@ KTEXT_PAGE_END
 	testl	%eax,%eax
 	jnz	.Lintr_xrstor_faulted
 .Lintr_restore_fsbase:		/* CPU doesn't have curproc's FS.base */
-	orl	$CPUF_USERSEGS,CPUVAR(FLAGS)
+	orl	$CPUPF_USERSEGS,CPUVAR(PFLAGS)
 	movq	CPUVAR(CURPCB),%rdx
 	movq	PCB_FSBASE(%rdx),%rdx
 	movl	%edx,%eax
diff --git a/sys/arch/amd64/amd64/machdep.c b/sys/arch/amd64/amd64/machdep.c
index 53e2e0a0aee..932b1dfeb47 100644
--- a/sys/arch/amd64/amd64/machdep.c
+++ b/sys/arch/amd64/amd64/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.278 2022/06/29 07:51:54 kettenis Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.279 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: machdep.c,v 1.3 2003/05/07 22:58:18 fvdl Exp $	*/
 
 /*-
@@ -604,8 +604,8 @@ sendsig(sig_t catcher, int sig, sigset_t mask, const siginfo_t *ksip,
 	sss = (sizeof(ksc) + 15) & ~15;
 
 	/* Save FPU state to PCB if necessary, then copy it out */
-	if (curcpu()->ci_flags & CPUF_USERXSTATE) {
-		curcpu()->ci_flags &= ~CPUF_USERXSTATE;
+	if (curcpu()->ci_pflags & CPUPF_USERXSTATE) {
+		curcpu()->ci_pflags &= ~CPUPF_USERXSTATE;
 		fpusavereset(&p->p_addr->u_pcb.pcb_savefpu);
 	}
 	sp -= fpu_save_len;
@@ -646,7 +646,7 @@ sendsig(sig_t catcher, int sig, sigset_t mask, const siginfo_t *ksip,
 	tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL);
 
 	/* The reset state _is_ the userspace state for this thread now */
-	curcpu()->ci_flags |= CPUF_USERXSTATE;
+	curcpu()->ci_pflags |= CPUPF_USERXSTATE;
 
 	return 0;
 }
@@ -694,8 +694,8 @@ sys_sigreturn(struct proc *p, void *v, register_t *retval)
 		return (EINVAL);
 
 	/* Current state is obsolete; toss it and force a reload */
-	if (curcpu()->ci_flags & CPUF_USERXSTATE) {
-		curcpu()->ci_flags &= ~CPUF_USERXSTATE;
+	if (curcpu()->ci_pflags & CPUPF_USERXSTATE) {
+		curcpu()->ci_pflags &= ~CPUPF_USERXSTATE;
 		fpureset();
 	}
 
@@ -1110,8 +1110,8 @@ reset_segs(void)
 	 * This operates like the cpu_switchto() sequence: if we
 	 * haven't reset %[defg]s already, do so now.
 	*/
-	if (curcpu()->ci_flags & CPUF_USERSEGS) {
-		curcpu()->ci_flags &= ~CPUF_USERSEGS;
+	if (curcpu()->ci_pflags & CPUPF_USERSEGS) {
+		curcpu()->ci_pflags &= ~CPUPF_USERSEGS;
 		__asm volatile(
 		    "movw %%ax,%%ds\n\t"
 		    "movw %%ax,%%es\n\t"
@@ -1137,12 +1137,12 @@ setregs(struct proc *p, struct exec_package *pack, u_long stack,
 	memcpy(&p->p_addr->u_pcb.pcb_savefpu,
 	    &proc0.p_addr->u_pcb.pcb_savefpu, fpu_save_len);
 
-	if (curcpu()->ci_flags & CPUF_USERXSTATE) {
+	if (curcpu()->ci_pflags & CPUPF_USERXSTATE) {
 		/* state in CPU is obsolete; reset it */
 		fpureset();
 	} else {
 		/* the reset state _is_ the userspace state now */
-		curcpu()->ci_flags |= CPUF_USERXSTATE;
+		curcpu()->ci_pflags |= CPUPF_USERXSTATE;
 	}
 
 	/* To reset all registers we have to return via iretq */
diff --git a/sys/arch/amd64/amd64/vm_machdep.c b/sys/arch/amd64/amd64/vm_machdep.c
index e8c7ac59f29..212865a1c61 100644
--- a/sys/arch/amd64/amd64/vm_machdep.c
+++ b/sys/arch/amd64/amd64/vm_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vm_machdep.c,v 1.45 2022/02/05 09:37:06 kettenis Exp $	*/
+/*	$OpenBSD: vm_machdep.c,v 1.46 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: vm_machdep.c,v 1.1 2003/04/26 18:39:33 fvdl Exp $	*/
 
 /*-
@@ -72,7 +72,7 @@ cpu_fork(struct proc *p1, struct proc *p2, void *stack, void *tcb,
 	struct switchframe *sf;
 
 	/* Save the fpu h/w state to p1's pcb so that we can copy it. */
-	if (p1 != &proc0 && (ci->ci_flags & CPUF_USERXSTATE))
+	if (p1 != &proc0 && (ci->ci_pflags & CPUPF_USERXSTATE))
 		fpusave(&pcb1->pcb_savefpu);
 
 	p2->p_md.md_flags = p1->p_md.md_flags;
diff --git a/sys/arch/amd64/amd64/vmm.c b/sys/arch/amd64/amd64/vmm.c
index 84da19438b7..354cfac206f 100644
--- a/sys/arch/amd64/amd64/vmm.c
+++ b/sys/arch/amd64/amd64/vmm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmm.c,v 1.318 2022/07/12 04:52:38 jsg Exp $	*/
+/*	$OpenBSD: vmm.c,v 1.319 2022/08/07 23:56:06 guenther Exp $	*/
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -1548,7 +1548,7 @@ start_vmm_on_cpu(struct cpu_info *ci)
 		}
 	}
 
-	ci->ci_flags |= CPUF_VMM;
+	atomic_setbits_int(&ci->ci_flags, CPUF_VMM);
 }
 
 /*
@@ -1587,7 +1587,7 @@ stop_vmm_on_cpu(struct cpu_info *ci)
 		lcr4(cr4);
 	}
 
-	ci->ci_flags &= ~CPUF_VMM;
+	atomic_clearbits_int(&ci->ci_flags, CPUF_VMM);
 }
 
 /*
@@ -4632,8 +4632,8 @@ vmm_fpurestore(struct vcpu *vcpu)
 	rw_assert_wrlock(&vcpu->vc_lock);
 
 	/* save vmm's FPU state if we haven't already */
-	if (ci->ci_flags & CPUF_USERXSTATE) {
-		ci->ci_flags &= ~CPUF_USERXSTATE;
+	if (ci->ci_pflags & CPUPF_USERXSTATE) {
+		ci->ci_pflags &= ~CPUPF_USERXSTATE;
 		fpusavereset(&curproc->p_addr->u_pcb.pcb_savefpu);
 	}
 
diff --git a/sys/arch/amd64/include/cpu.h b/sys/arch/amd64/include/cpu.h
index 6916915a446..e504cea14c2 100644
--- a/sys/arch/amd64/include/cpu.h
+++ b/sys/arch/amd64/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.145 2022/07/12 04:46:00 jsg Exp $	*/
+/*	$OpenBSD: cpu.h,v 1.146 2022/08/07 23:56:06 guenther Exp $	*/
 /*	$NetBSD: cpu.h,v 1.1 2003/04/26 18:39:39 fvdl Exp $	*/
 
 /*-
@@ -89,6 +89,12 @@ union vmm_cpu_cap {
 	struct svm vcc_svm;
 };
 
+/*
+ *  Locks used to protect struct members in this file:
+ *	I	immutable after creation
+ *	a	atomic operations
+ *	o	owned (read/modified only) by this CPU
+ */
 struct x86_64_tss;
 struct cpu_info {
 	/*
@@ -98,32 +104,36 @@ struct cpu_info {
 	 * the part that is *not* visible begins, so don't put anything
 	 * above it that must be kept hidden from userspace!
 	 */
-	u_int64_t	ci_kern_cr3;	/* U+K page table */
-	u_int64_t	ci_scratch;	/* for U<-->K transition */
+	u_int64_t	ci_kern_cr3;	/* [o] U+K page table */
+	u_int64_t	ci_scratch;	/* [o] for U<-->K transition */
 
 #define ci_PAGEALIGN	ci_dev
-	struct device *ci_dev;
-	struct cpu_info *ci_self;
+	struct device *ci_dev;		/* [I] */
+	struct cpu_info *ci_self;	/* [I] */
 	struct schedstate_percpu ci_schedstate; /* scheduler state */
-	struct cpu_info *ci_next;
+	struct cpu_info *ci_next;	/* [I] */
 
-	struct proc *ci_curproc;
-	u_int ci_cpuid;
-	u_int ci_apicid;
-	u_int ci_acpi_proc_id;
-	u_int32_t ci_randseed;
+	struct proc *ci_curproc;	/* [o] */
+	u_int ci_cpuid;			/* [I] */
+	u_int ci_apicid;		/* [I] */
+	u_int ci_acpi_proc_id;		/* [I] */
+	u_int32_t ci_randseed;		/* [o] */
 
-	u_int64_t ci_kern_rsp;	/* kernel-only stack */
-	u_int64_t ci_intr_rsp;	/* U<-->K trampoline stack */
-	u_int64_t ci_user_cr3;	/* U-K page table */
+	u_int64_t ci_kern_rsp;		/* [o] kernel-only stack */
+	u_int64_t ci_intr_rsp;		/* [o] U<-->K trampoline stack */
+	u_int64_t ci_user_cr3;		/* [o] U-K page table */
 
 	/* bits for mitigating Micro-architectural Data Sampling */
-	char		ci_mds_tmp[32];		/* 32byte aligned */
-	void		*ci_mds_buf;
+	char		ci_mds_tmp[32];	/* [o] 32byte aligned */
+	void		*ci_mds_buf;	/* [I] */
 
 	struct pmap *ci_proc_pmap;	/* last userspace pmap */
-	struct pcb *ci_curpcb;
-	struct pcb *ci_idle_pcb;
+	struct pcb *ci_curpcb;		/* [o] */
+	struct pcb *ci_idle_pcb;	/* [o] */
+
+	u_int	ci_pflags;		/* [o] */
+#define CPUPF_USERSEGS		0x01	/* CPU has curproc's segs and FS.base */
+#define CPUPF_USERXSTATE	0x02	/* CPU has curproc's xsave state */
 
 	struct intrsource *ci_isources[MAX_INTR_SOURCES];
 	u_int64_t	ci_ipending;
@@ -136,38 +146,37 @@ struct cpu_info {
 	int		ci_mutex_level;
 #endif
 
-	volatile u_int	ci_flags;
-	u_int32_t	ci_ipis;
-
-	u_int32_t	ci_feature_flags;
-	u_int32_t	ci_feature_eflags;
-	u_int32_t	ci_feature_sefflags_ebx;
-	u_int32_t	ci_feature_sefflags_ecx;
-	u_int32_t	ci_feature_sefflags_edx;
-	u_int32_t	ci_feature_amdspec_ebx;
-	u_int32_t	ci_feature_tpmflags;
-	u_int32_t	ci_pnfeatset;
-	u_int32_t	ci_efeature_eax;
-	u_int32_t	ci_efeature_ecx;
-	u_int32_t	ci_brand[12];
-	u_int32_t	ci_signature;
-	u_int32_t	ci_family;
-	u_int32_t	ci_model;
-	u_int32_t	ci_cflushsz;
-
-	int		ci_inatomic;
+	volatile u_int	ci_flags;	/* [a] */
+	u_int32_t	ci_ipis;	/* [a] */
+
+	u_int32_t	ci_feature_flags;	/* [I] */
+	u_int32_t	ci_feature_eflags;	/* [I] */
+	u_int32_t	ci_feature_sefflags_ebx;/* [I] */
+	u_int32_t	ci_feature_sefflags_ecx;/* [I] */
+	u_int32_t	ci_feature_sefflags_edx;/* [I] */
+	u_int32_t	ci_feature_amdspec_ebx;	/* [I] */
+	u_int32_t	ci_feature_tpmflags;	/* [I] */
+	u_int32_t	ci_pnfeatset;		/* [I] */
+	u_int32_t	ci_efeature_eax;	/* [I] */
+	u_int32_t	ci_efeature_ecx;	/* [I] */
+	u_int32_t	ci_brand[12];		/* [I] */
+	u_int32_t	ci_signature;		/* [I] */
+	u_int32_t	ci_family;		/* [I] */
+	u_int32_t	ci_model;		/* [I] */
+	u_int32_t	ci_cflushsz;		/* [I] */
+
+	int		ci_inatomic;		/* [o] */
 
 #define __HAVE_CPU_TOPOLOGY
-	u_int32_t	ci_smt_id;
-	u_int32_t	ci_core_id;
-	u_int32_t	ci_pkg_id;
+	u_int32_t	ci_smt_id;		/* [I] */
+	u_int32_t	ci_core_id;		/* [I] */
+	u_int32_t	ci_pkg_id;		/* [I] */
 
-	struct cpu_functions *ci_func;
-	void (*cpu_setup)(struct cpu_info *);
-	void (*ci_info)(struct cpu_info *);
+	struct cpu_functions *ci_func;		/* [I] */
+	void (*cpu_setup)(struct cpu_info *);	/* [I] */
 
-	struct device	*ci_acpicpudev;
-	volatile u_int	ci_mwait;
+	struct device	*ci_acpicpudev;		/* [I] */
+	volatile u_int	ci_mwait;		/* [a] */
 #define	MWAIT_IN_IDLE		0x1	/* don't need IPI to wake */
 #define	MWAIT_KEEP_IDLING	0x2	/* cleared by other cpus to wake me */
 #define	MWAIT_ONLY		0x4	/* set if all idle states use mwait */
@@ -175,8 +184,8 @@ struct cpu_info {
 
 	int		ci_want_resched;
 
-	struct	x86_64_tss *ci_tss;
-	void		*ci_gdt;
+	struct	x86_64_tss *ci_tss;		/* [o] */
+	void		*ci_gdt;		/* [o] */
 
 	volatile int	ci_ddb_paused;
 #define CI_DDB_RUNNING		0
@@ -224,9 +233,7 @@ struct cpu_info {
 #define CPUF_IDENTIFIED	0x0020		/* CPU has been identified */
 
 #define CPUF_CONST_TSC	0x0040		/* CPU has constant TSC */
-#define CPUF_USERSEGS	0x0080		/* CPU has curproc's segs and FS.base */
 #define CPUF_INVAR_TSC	0x0100		/* CPU has invariant TSC */
-#define CPUF_USERXSTATE	0x0200		/* CPU has curproc's xsave state */
 
 #define CPUF_SYNCTSC	0x0800		/* Synchronize TSC */
 #define CPUF_PRESENT	0x1000		/* CPU is present */