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cpu_physical_memory_write_rom() needs to do TB invalidates
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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()
doesn't 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 <david@gibson.dropbear.id.au>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
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dgibson authored and Anthony Liguori committed Sep 17, 2012
1 parent bbdd2ad commit 0b57e28
Showing 1 changed file with 7 additions and 0 deletions.
7 changes: 7 additions & 0 deletions exec.c
Expand Up @@ -3536,6 +3536,13 @@ 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));
}
qemu_put_ram_ptr(ptr);
}
len -= l;
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