diff options
| author | Alex Bennée <alex.bennee@linaro.org> | 2021-11-29 14:09:26 +0000 |
|---|---|---|
| committer | Alex Bennée <alex.bennee@linaro.org> | 2021-11-29 15:12:37 +0000 |
| commit | aff0e204cb1f1c036a496c94c15f5dfafcd9b4b4 (patch) | |
| tree | 3b7ca5c6f32f9635df139d4961c2c2aaa87d9007 /accel | |
| parent | 48e14066ac10581db4e69f75eda107cfdafa6022 (diff) | |
| download | qemu-aff0e204cb1f1c036a496c94c15f5dfafcd9b4b4.zip | |
accel/tcg: suppress IRQ check for special TBs
When we set cpu->cflags_next_tb it is because we want to carefully
control the execution of the next TB. Currently there is a race that
causes the second stage of watchpoint handling to get ignored if an
IRQ is processed before we finish executing the instruction that
triggers the watchpoint. Use the new CF_NOIRQ facility to avoid the
race.
We also suppress IRQs when handling precise self modifying code to
avoid unnecessary bouncing.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Pavel Dovgalyuk <pavel.dovgalyuk@ispras.ru>
Fixes: https://gitlab.com/qemu-project/qemu/-/issues/245
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211129140932.4115115-3-alex.bennee@linaro.org>
Diffstat (limited to 'accel')
| -rw-r--r-- | accel/tcg/cpu-exec.c | 9 | ||||
| -rw-r--r-- | accel/tcg/translate-all.c | 4 |
2 files changed, 11 insertions, 2 deletions
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index 2d14d02f6c..409ec8c38c 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -721,6 +721,15 @@ static inline bool need_replay_interrupt(int interrupt_request) static inline bool cpu_handle_interrupt(CPUState *cpu, TranslationBlock **last_tb) { + /* + * If we have requested custom cflags with CF_NOIRQ we should + * skip checking here. Any pending interrupts will get picked up + * by the next TB we execute under normal cflags. + */ + if (cpu->cflags_next_tb != -1 && cpu->cflags_next_tb & CF_NOIRQ) { + return false; + } + /* Clear the interrupt flag now since we're processing * cpu->interrupt_request and cpu->exit_request. * Ensure zeroing happens before reading cpu->exit_request or diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c index bd0bb81d08..bd71db59a9 100644 --- a/accel/tcg/translate-all.c +++ b/accel/tcg/translate-all.c @@ -1738,7 +1738,7 @@ tb_invalidate_phys_page_range__locked(struct page_collection *pages, if (current_tb_modified) { page_collection_unlock(pages); /* Force execution of one insn next time. */ - cpu->cflags_next_tb = 1 | curr_cflags(cpu); + cpu->cflags_next_tb = 1 | CF_NOIRQ | curr_cflags(cpu); mmap_unlock(); cpu_loop_exit_noexc(cpu); } @@ -1906,7 +1906,7 @@ static bool tb_invalidate_phys_page(tb_page_addr_t addr, uintptr_t pc) #ifdef TARGET_HAS_PRECISE_SMC if (current_tb_modified) { /* Force execution of one insn next time. */ - cpu->cflags_next_tb = 1 | curr_cflags(cpu); + cpu->cflags_next_tb = 1 | CF_NOIRQ | curr_cflags(cpu); return true; } #endif |