Align stack to 16 bytes to avoid SIGBUS (#207)

Since callbackasm1 returns to the caller of its caller it wasn't aligning the stack to 16 bytes which is required by the AMD64 calling convention.

Closes #193

commit: 50210c67e1f7247e6d01390a147d5a691d09d1d1
author: TotallyGamerJet · 2y ago · 2024-01-27 15:25 UTC
committer: GitHub · 2y ago · 2024-01-27 15:25 UTC
parent: e5188d3
signature: GPG UnverifiedB5690EEEBB952194 The key is unknown

3 files · +8 -11

M .github/workflows/test.yml +2 -2


@@ -7,7 +7,7 @@ jobs:
7	7		strategy:
8	8		matrix:
9	9		os: [ubuntu-latest, macos-latest, windows-latest]
10		-	go: ['1.18.x', '1.19.x', '1.20.x', '1.21.x']
	10	+	go: ['1.18.x', '1.19.x', '1.20.x', '1.21.x', '1.22.0-rc.2']
11	11		name: Test with Go ${{ matrix.go }} on ${{ matrix.os }}
12	12		runs-on: ${{ matrix.os }}
13	13		defaults:

@@ -110,7 +110,7 @@ jobs:
110	110		freebsd:
111	111		strategy:
112	112		matrix:
113		-	go: ['1.18.10', '1.19.12', '1.20.7', '1.21.0']
	113	+	go: ['1.18.10', '1.19.12', '1.20.7', '1.21.0', '1.22rc2']
114	114		name: Test with Go ${{ matrix.go }} on FreeBSD
115	115		runs-on: ubuntu-22.04
116	116		defaults:


@@ -7,7 +7,7 @@ jobs:
7		strategy:	7		strategy:
8		matrix:	8		matrix:
9		os: [ubuntu-latest, macos-latest, windows-latest]	9		os: [ubuntu-latest, macos-latest, windows-latest]
10	-	go: ['1.18.x', '1.19.x', '1.20.x', '1.21.x']	10	+	go: ['1.18.x', '1.19.x', '1.20.x', '1.21.x', '1.22.0-rc.2']
11		name: Test with Go ${{ matrix.go }} on ${{ matrix.os }}	11		name: Test with Go ${{ matrix.go }} on ${{ matrix.os }}
12		runs-on: ${{ matrix.os }}	12		runs-on: ${{ matrix.os }}
13		defaults:	13		defaults:

@@ -110,7 +110,7 @@ jobs:
110		freebsd:	110		freebsd:
111		strategy:	111		strategy:
112		matrix:	112		matrix:
113	-	go: ['1.18.10', '1.19.12', '1.20.7', '1.21.0']	113	+	go: ['1.18.10', '1.19.12', '1.20.7', '1.21.0', '1.22rc2']
114		name: Test with Go ${{ matrix.go }} on FreeBSD	114		name: Test with Go ${{ matrix.go }} on FreeBSD
115		runs-on: ubuntu-22.04	115		runs-on: ubuntu-22.04
116		defaults:	116		defaults:

M internal/fakecgo/asm_amd64.s +1 -1


@@ -10,7 +10,7 @@
10	10		// Saves C callee-saved registers and calls cgocallback with three arguments.
11	11		// fn is the PC of a func(a unsafe.Pointer) function.
12	12		// This signature is known to SWIG, so we can't change it.
13		-	TEXT crosscall2(SB), NOSPLIT\|NOFRAME, $0-0
	13	+	TEXT crosscall2(SB), NOSPLIT, $0-0
14	14		PUSH_REGS_HOST_TO_ABI0()
15	15
16	16		// Make room for arguments to cgocallback.


@@ -10,7 +10,7 @@
10		// Saves C callee-saved registers and calls cgocallback with three arguments.	10		// Saves C callee-saved registers and calls cgocallback with three arguments.
11		// fn is the PC of a func(a unsafe.Pointer) function.	11		// fn is the PC of a func(a unsafe.Pointer) function.
12		// This signature is known to SWIG, so we can't change it.	12		// This signature is known to SWIG, so we can't change it.
13	-	TEXT crosscall2(SB), NOSPLIT\|NOFRAME, $0-0	13	+	TEXT crosscall2(SB), NOSPLIT, $0-0
14		PUSH_REGS_HOST_TO_ABI0()	14		PUSH_REGS_HOST_TO_ABI0()
15			15
16		// Make room for arguments to cgocallback.	16		// Make room for arguments to cgocallback.

M sys_amd64.s +5 -8


@@ -96,11 +96,9 @@ TEXT syscall15X(SB), NOSPLIT\|NOFRAME, $0
96	96		RET
97	97
98	98		TEXT callbackasm1(SB), NOSPLIT\|NOFRAME, $0
99		-	// remove return address from stack, we are not returning to callbackasm, but to its caller.
100		-	MOVQ 0(SP), AX
101		-	ADDQ $8, SP
102		-
103		-	MOVQ 0(SP), R10 // get the return SP so that we can align register args with stack args
	99	+	MOVQ 0(SP), AX // save the return address to calculate the cb index
	100	+	MOVQ 8(SP), R10 // get the return SP so that we can align register args with stack args
	101	+	ADDQ $8, SP // remove return address from stack, we are not returning to callbackasm, but to its caller.
104	102
105	103		// make space for first six int and 8 float arguments below the frame
106	104		ADJSP $14*8, SP

@@ -120,7 +118,7 @@ TEXT callbackasm1(SB), NOSPLIT\|NOFRAME, $0
120	118		MOVQ R9, (14*8)(SP)
121	119		LEAQ 8(SP), R8 // R8 = address of args vector
122	120
123		-	MOVQ R10, 0(SP) // push the stack pointer below registers
	121	+	PUSHQ R10 // push the stack pointer below registers
124	122
125	123		// determine index into runtime·cbs table
126	124		MOVQ $callbackasm(SB), DX

@@ -156,8 +154,7 @@ TEXT callbackasm1(SB), NOSPLIT\|NOFRAME, $0
156	154
157	155		POP_REGS_HOST_TO_ABI0()
158	156
159		-	MOVQ 0(SP), R10 // get the SP back
160		-
	157	+	POPQ R10 // get the SP back
161	158		ADJSP $-14*8, SP // remove arguments
162	159
163	160		MOVQ R10, 0(SP)

 	RET
 TEXT callbackasm1(SB), NOSPLIT|NOFRAME, $0
-	// remove return address from stack, we are not returning to callbackasm, but to its caller.
+	MOVQ 0(SP), AX  // save the return address to calculate the cb index
-	MOVQ 0(SP), AX
+	MOVQ 8(SP), R10 // get the return SP so that we can align register args with stack args
-	ADDQ $8, SP
+	ADDQ $8, SP     // remove return address from stack, we are not returning to callbackasm, but to its caller.
-	MOVQ 0(SP), R10 // get the return SP so that we can align register args with stack args
 	// make space for first six int and 8 float arguments below the frame
 	ADJSP $14*8, SP
 	MOVQ  R9, (14*8)(SP)
 	LEAQ  8(SP), R8      // R8 = address of args vector
-	MOVQ R10, 0(SP) // push the stack pointer below registers
+	PUSHQ R10 // push the stack pointer below registers
 	// determine index into runtime·cbs table
 	MOVQ $callbackasm(SB), DX
 	POP_REGS_HOST_TO_ABI0()
-	MOVQ 0(SP), R10 // get the SP back
+	POPQ  R10        // get the SP back
 	ADJSP $-14*8, SP // remove arguments
 	MOVQ R10, 0(SP)