motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-10 02:54:58 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

tcg/aarch64: Reorg goto_tb implementation

Browse source 
The old implementation replaces two insns, swapping between

	b	<dest>
	nop
	br	x30
and
	adrp	x30, <dest>
	addi	x30, x30, lo12:<dest>
	br	x30

There is a race condition in which a thread could be stopped at
the PC of the second insn, and when restarted does not see the
complete address computation and branches to nowhere.

The new implemetation replaces only one insn, swapping between

	b	<dest>
	br	tmp
and
	ldr	tmp, <jmp_addr>
	br	tmp

Reported-by: hev <r@hev.cc>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2022-12-05 17:26:23 -06:00
parent 2fd2e78d1b
commit d59d83a1c3
2 changed files with 29 additions and 39 deletions
Download patch file Download diff file Expand all files Collapse all files

2
tcg/aarch64/tcg-target.h
View file

@ -15,7 +15,7 @@
#define TCG_TARGET_INSN_UNIT_SIZE 4
#define TCG_TARGET_TLB_DISPLACEMENT_BITS 24
#define MAX_CODE_GEN_BUFFER_SIZE (2 * GiB)
#define MAX_CODE_GEN_BUFFER_SIZE ((size_t)-1)
typedef enum {
TCG_REG_X0, TCG_REG_X1, TCG_REG_X2, TCG_REG_X3,