From: Alex Bennée <alex.ben...@linaro.org> The mmio path (see exec.c:prepare_mmio_access) already protects itself against recursive locking and it makes sense to do the same for io_readx/writex. Otherwise any helper running in the BQL context will assert when it attempts to write to device memory as in the case of the bug report.
Reviewed-by: Peter Maydell <peter.mayd...@linaro.org> Signed-off-by: Alex Bennée <alex.ben...@linaro.org> CC: Richard Jones <rjo...@redhat.com> CC: Paolo Bonzini <bonz...@gnu.org> CC: qemu-sta...@nongnu.org Message-Id: <20170921110625.9500-1-alex.ben...@linaro.org> Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- accel/tcg/cputlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c index e72415a882..bcbcc4db6c 100644 --- a/accel/tcg/cputlb.c +++ b/accel/tcg/cputlb.c @@ -765,7 +765,7 @@ static uint64_t io_readx(CPUArchState *env, CPUIOTLBEntry *iotlbentry, cpu->mem_io_vaddr = addr; - if (mr->global_locking) { + if (mr->global_locking && !qemu_mutex_iothread_locked()) { qemu_mutex_lock_iothread(); locked = true; } @@ -800,7 +800,7 @@ static void io_writex(CPUArchState *env, CPUIOTLBEntry *iotlbentry, cpu->mem_io_vaddr = addr; cpu->mem_io_pc = retaddr; - if (mr->global_locking) { + if (mr->global_locking && !qemu_mutex_iothread_locked()) { qemu_mutex_lock_iothread(); locked = true; } -- 2.13.5