git: a6deeaa2fb3b - main - dtrace/arm64: Fix copyout and copyoutstr

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=a6deeaa2fb3b28a61ae56a85f2275f67fcf23262

commit a6deeaa2fb3b28a61ae56a85f2275f67fcf23262
Author:     Benjamin Jacobs <freebsd@dev.thsi.be>
AuthorDate: 2026-09-16 13:07:01 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2026-09-21 00:04:43 +0000

    dtrace/arm64: Fix copyout and copyoutstr
    
    Calling dtrace_copy and dtrace_copystr with the kaddr and uaddr
    arguments inversed does not work with PAN. Rename them
    dtrace_copyin_pan and dtrace_copyinstr_pan, respectively, and
    implement dtrace_copyout_pan and dtrace_copyoutstr_pan.
    
    Avoid excessive faulting by checkin DTrace's CPU flags. Implement the
    trick from OpenSolaris/Illumos of only checking the flags when
    crossing into a new page, altough more effectively by examining the
    vaddr instead of the count.
    
    Reviewed by:    markj
    MFC after:      3 weeks
    Differential Revision:  https://reviews.freebsd.org/D59449
---
 .../opensolaris/uts/common/sys/dtrace_impl.h       |  7 +++
 sys/cddl/dev/dtrace/aarch64/dtrace_asm.S           | 68 ++++++++++++++++++++--
 sys/cddl/dev/dtrace/aarch64/dtrace_isa.c           |  8 +--
 3 files changed, 73 insertions(+), 10 deletions(-)

diff --git a/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace_impl.h b/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace_impl.h
index c26956a646ff..88d3d88ddfcb 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace_impl.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace_impl.h
@@ -1302,8 +1302,15 @@ extern int dtrace_attached(void);
 extern hrtime_t dtrace_gethrestime(void);
 #endif
 
+#if defined(__aarch64__)
+extern void dtrace_copyin_pan(uintptr_t, uintptr_t, size_t);
+extern void dtrace_copyinstr_pan(uintptr_t, uintptr_t, size_t);
+extern void dtrace_copyout_pan(uintptr_t, uintptr_t, size_t, volatile uint16_t *);
+extern void dtrace_copyoutstr_pan(uintptr_t, uintptr_t, size_t, volatile uint16_t *);
+#else
 extern void dtrace_copy(uintptr_t, uintptr_t, size_t);
 extern void dtrace_copystr(uintptr_t, uintptr_t, size_t, volatile uint16_t *);
+#endif
 
 /*
  * DTrace Assertions
diff --git a/sys/cddl/dev/dtrace/aarch64/dtrace_asm.S b/sys/cddl/dev/dtrace/aarch64/dtrace_asm.S
index decca6f79e0c..e27974eecc8f 100644
--- a/sys/cddl/dev/dtrace/aarch64/dtrace_asm.S
+++ b/sys/cddl/dev/dtrace/aarch64/dtrace_asm.S
@@ -104,9 +104,9 @@ END(dtrace_fuword64_nocheck)
 
 /*
 void
-dtrace_copy(uintptr_t uaddr, uintptr_t kaddr, size_t size)
+dtrace_copyin_pan(uintptr_t uaddr, uintptr_t kaddr, size_t size)
 */
-ENTRY(dtrace_copy)
+ENTRY(dtrace_copyin_pan)
 	cbz	x2, 2f		/* If len == 0 then skip loop */
 1:
 	mvn	x4, xzr		/* Set all bits */
@@ -119,13 +119,13 @@ ENTRY(dtrace_copy)
 	cbnz	x2, 1b
 2:
 	RET
-END(dtrace_copy)
+END(dtrace_copyin_pan)
 
 /*
 void
-dtrace_copystr(uintptr_t uaddr, uintptr_t kaddr, size_t size)
+dtrace_copyinstr_pan(uintptr_t uaddr, uintptr_t kaddr, size_t size)
 */
-ENTRY(dtrace_copystr)
+ENTRY(dtrace_copyinstr_pan)
 	cbz     x2, 2f          /* If len == 0 then skip loop */
 1:
 	mvn	x4, xzr		/* Set all bits */
@@ -139,7 +139,63 @@ ENTRY(dtrace_copystr)
 	cbnz    x2, 1b
 2:
 	RET
-END(dtrace_copystr)
+END(dtrace_copyinstr_pan)
+
+/*
+void
+dtrace_copyout_pan(uintptr_t kaddr, uintptr_t uaddr, size_t size,
+    volatile uint16_t *flags)
+*/
+ENTRY(dtrace_copyout_pan)
+	cbz	x2, 4f		/* If len == 0 then skip loop */
+	ldrb	w4, [x0], #1	/* Load from kaddr */
+	sttrb	w4, [x1]	/* Store in uaddr or raise data abort */
+	b 2f			/* Check fault */
+1:
+	ldrb	w4, [x0], #1	/* Load from kaddr */
+	sttrb	w4, [x1]	/* Store in uaddr or raise data abort */
+	tst	x1, #0xfff	/* uaddr & 2^12-1 */
+	bne	3f		/* If not 4k aligned then skip check */
+2:
+	ldrh	w5, [x3]	/* Load cpu flags */
+	tst	w5, #CPU_DTRACE_BADADDR
+	bne	4f		/* If flags&CPU_DTRACE_BADADDR != 0 then break */
+3:
+	add	x1, x1, #1	/* uaddr++ */
+	sub	x2, x2, #1	/* len-- */
+	cbnz	x2, 1b
+4:
+	RET
+END(dtrace_copyout_pan)
+
+
+/*
+void
+dtrace_copyoutstr_pan(uintptr_t kaddr, uintptr_t uaddr, size_t size,
+    volatile uint16_t *flags)
+*/
+ENTRY(dtrace_copyoutstr_pan)
+	cbz	x2, 4f		/* If len == 0 then skip loop */
+	ldrb	w4, [x0], #1	/* Load from kaddr */
+	sttrb	w4, [x1]	/* Store in uaddr or raise data abort */
+	b 2f			/* Check fault */
+1:
+	ldrb	w4, [x0], #1	/* Load from kaddr */
+	sttrb	w4, [x1]	/* Store in uaddr or raise data abort */
+	tst	x1, #0xfff	/* uaddr & 2^12-1 */
+	bne	3f		/* If not 4k aligned then skip check */
+2:
+	ldrh	w5, [x3]	/* Load cpu flags */
+	tst	w5, #CPU_DTRACE_BADADDR
+	bne	4f		/* If flags&CPU_DTRACE_BADADDR != 0 then break */
+3:
+	cbz     w4, 4f          /* If == 0 then break */
+	add	x1, x1, #1	/* uaddr++ */
+	sub	x2, x2, #1	/* len-- */
+	cbnz	x2, 1b
+4:
+	RET
+END(dtrace_copyoutstr_pan)
 
 /*
 uintptr_t
diff --git a/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c b/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c
index 037d4734659e..80998af3f0f4 100644
--- a/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c
+++ b/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c
@@ -351,7 +351,7 @@ dtrace_copyin(uintptr_t uaddr, uintptr_t kaddr, size_t size,
 {
 
 	if (dtrace_copycheck(uaddr, kaddr, size))
-		dtrace_copy(uaddr, kaddr, size);
+		dtrace_copyin_pan(uaddr, kaddr, size);
 }
 
 void
@@ -360,7 +360,7 @@ dtrace_copyout(uintptr_t kaddr, uintptr_t uaddr, size_t size,
 {
 
 	if (dtrace_copycheck(uaddr, kaddr, size))
-		dtrace_copy(kaddr, uaddr, size);
+		dtrace_copyout_pan(kaddr, uaddr, size, flags);
 }
 
 void
@@ -369,7 +369,7 @@ dtrace_copyinstr(uintptr_t uaddr, uintptr_t kaddr, size_t size,
 {
 
 	if (dtrace_copycheck(uaddr, kaddr, size))
-		dtrace_copystr(uaddr, kaddr, size, flags);
+		dtrace_copyinstr_pan(uaddr, kaddr, size);
 }
 
 void
@@ -378,7 +378,7 @@ dtrace_copyoutstr(uintptr_t kaddr, uintptr_t uaddr, size_t size,
 {
 
 	if (dtrace_copycheck(uaddr, kaddr, size))
-		dtrace_copystr(kaddr, uaddr, size, flags);
+		dtrace_copyoutstr_pan(kaddr, uaddr, size, flags);
 }
 
 uint8_t