powerpc: Fix __flush_icache_range on 44x
The ptrace POKETEXT interface allows a process to modify the text pages of
a child process being ptraced, usually to insert breakpoints via trap
instructions. The kernel eventually calls copy_to_user_page, which in turn
calls __flush_icache_range to invalidate the icache lines for the child
process.
However, this function does not work on 44x due to the icache being virtually
indexed. This was noticed by a breakpoint being triggered after it had been
cleared by ltrace on a 440EPx board. The convenient solution is to do a
flash invalidate of the icache in the __flush_icache_range function.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
1 file changed