On 22.08.2012, at 06:59, David Gibson wrote: > cpu_physical_memory_write_rom(), despite the name, can also be used to > write images into RAM - and will often be used that way if the machine > uses load_image_targphys() into RAM addresses. > > However, cpu_physical_memory_write_rom(), unlike cpu_physical_memory_rw() > does invalidate any cached TBs which might be affected by the region > written. > > This was breaking reset (under full emu) on the pseries machine - we loaded > our firmware image into RAM, and while executing it rewrite the code at > the entry point (correctly causing a TB invalidate/refresh). When we > reset the firmware image was reloaded, but the TB from the rewrite was > still active and caused us to get an illegal instruction trap. > > This patch fixes the bug by duplicating the tb invalidate code from > cpu_physical_memory_rw() in cpu_physical_memory_write_rom(). > > Signed-off-by: David Gibson <da...@gibson.dropbear.id.au> > --- > exec.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/exec.c b/exec.c > index 5834766..eff40d7 100644 > --- a/exec.c > +++ b/exec.c > @@ -3523,6 +3523,13 @@ void cpu_physical_memory_write_rom(target_phys_addr_t > addr, > /* ROM/RAM case */ > ptr = qemu_get_ram_ptr(addr1); > memcpy(ptr, buf, l); > + if (!cpu_physical_memory_is_dirty(addr1)) { > + /* invalidate code */ > + tb_invalidate_phys_page_range(addr1, addr1 + l, 0); > + /* set dirty bit */ > + cpu_physical_memory_set_dirty_flags( > + addr1, (0xff & ~CODE_DIRTY_FLAG)); > + }
Can't we just call cpu_physical_memory_rw in the RAM case? The function only tries to not do MMIO accesses on ROM pages, right? Alex