Re: [PATCH] powerpc: Fix 4xx flush_tlb_page()

[Kumar Gala <galak@kernel.crashing.org>]

On Oct 29, 2007, at 5:46 PM, Benjamin Herrenschmidt wrote:

> On 4xx CPUs, the current implementation of flush_tlb_page() uses
> a low level _tlbie() assembly function that only works for the
> current PID. Thus, invalidations caused by, for example, a COW
> fault triggered by get_user_pages() from a different context will
> not work properly, causing among other things, gdb breakpoints
> to fail.
>
> This patch adds a "pid" argument to _tlbie() on 4xx processors,
> and uses it to flush entries in the right context. FSL BookE
> also gets the argument but it seems they don't need it (their
> tlbivax form ignores the PID when invalidating according to the
> document I have).
>
> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---
>
>  arch/powerpc/kernel/misc_32.S    |   23 ++++++++++++++++-------
>  arch/powerpc/mm/fault.c          |    2 +-
>  arch/powerpc/mm/mmu_decl.h       |    4 ++--
>  arch/ppc/kernel/misc.S           |   22 +++++++++++++++-------
>  arch/ppc/mm/fault.c              |    2 +-
>  arch/ppc/mm/mmu_decl.h           |    4 ++--
>  arch/ppc/platforms/4xx/ebony.c   |    2 +-
>  arch/ppc/platforms/4xx/ocotea.c  |    2 +-
>  arch/ppc/platforms/4xx/taishan.c |    2 +-
>  include/asm-powerpc/tlbflush.h   |   12 ++++++------
>  10 files changed, 46 insertions(+), 29 deletions(-)

Acked-by: Kumar Gala <galak@kernel.crashing.org>

- k