Re: [Qemu-devel] [PATCH] PPC: Fix large page support in TCG

[Alexander Graf <agraf@suse.de>]

On 03/03/2012 07:07 PM, Andreas Färber wrote:
> Am 03.03.2012 17:39, schrieb Nathan Whitehorn:
>> Fix large page support in TCG. The old code would overwrite the large
>> page table entry with the fake 4 KB
>> one generated here whenever the ref/change bits were updated, causing it
>> to point to the wrong area of memory. Instead of creating a fake PTE,
>> just update the real address at the end.
>>
>> Signed-off-by: Nathan Whitehorn<nwhitehorn@freebsd.org>
> cc'ing Alex and qemu-ppc.

David? Could you please ack?


Alex

> /-F
>
>> ---
>>   target-ppc/helper.c |   11 +++++------
>>   1 files changed, 5 insertions(+), 6 deletions(-)
>>
>> diff --git a/target-ppc/helper.c b/target-ppc/helper.c
>> index 928fbcf..0f5ad2e 100644
>> --- a/target-ppc/helper.c
>> +++ b/target-ppc/helper.c
>> @@ -597,12 +597,6 @@ static inline int _find_pte(CPUState *env,
>> mmu_ctx_t *ctx,
>> int is_64b, int h,
>>                   pte1 = ldq_phys(env->htab_base + pteg_off + (i * 16) + 8);
>>               }
>>
>> -            /* We have a TLB that saves 4K pages, so let's
>> -             * split a huge page to 4k chunks */
>> -            if (target_page_bits != TARGET_PAGE_BITS)
>> -                pte1 |= (ctx->eaddr&  (( 1<<  target_page_bits ) - 1))
>> -&  TARGET_PAGE_MASK;
>> -
>>               r = pte64_check(ctx, pte0, pte1, h, rw, type);
>>               LOG_MMU("Load pte from " TARGET_FMT_lx " =>  " TARGET_FMT_lx
>> ""
>>                       TARGET_FMT_lx " %d %d %d " TARGET_FMT_lx "\n",
>> @@ -678,6 +672,11 @@ static inline int _find_pte(CPUState *env,
>> mmu_ctx_t *ctx,
>> int is_64b, int h,
>>           }
>>       }
>>
>> +    /* We have a TLB that saves 4K pages, so let's
>> +     * split a huge page to 4k chunks */
>> +    if (target_page_bits != TARGET_PAGE_BITS)
>> +       ctx->raddr |= (ctx->eaddr&  (( 1<<  target_page_bits ) - 1))
>> +&  TARGET_PAGE_MASK;
>>       return ret;
>>   }
>>
>> -- 
>> 1.7.9