Re: [PATCH] KVM: PPC: e500: Fix default tlb for victim hint

[Alexander Graf <agraf@suse.de>]

On 30.06.14 20:18, Scott Wood wrote:
> On Mon, 2014-06-30 at 15:54 +0300, Mihai Caraman wrote:
>> Tlb search operation used for victim hint relies on the default tlb set by the
>> host. When hardware tablewalk support is enabled in the host, the default tlb is
>> TLB1 which leads KVM to evict the bolted entry. Set and restore the default tlb
>> when searching for victim hint.
>>
>> Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
>> ---
>>   arch/powerpc/include/asm/mmu-book3e.h | 5 ++++-
>>   arch/powerpc/kvm/e500_mmu_host.c      | 4 ++++
>>   2 files changed, 8 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/include/asm/mmu-book3e.h b/arch/powerpc/include/asm/mmu-book3e.h
>> index 901dac6..5dad378 100644
>> --- a/arch/powerpc/include/asm/mmu-book3e.h
>> +++ b/arch/powerpc/include/asm/mmu-book3e.h
>> @@ -40,7 +40,9 @@
>>   
>>   /* MAS registers bit definitions */
>>   
>> -#define MAS0_TLBSEL(x)		(((x) << 28) & 0x30000000)
>> +#define MAS0_TLBSEL_MASK        0x30000000
>> +#define MAS0_TLBSEL_SHIFT       28
>> +#define MAS0_TLBSEL(x)          (((x) << MAS0_TLBSEL_SHIFT) & MAS0_TLBSEL_MASK)
>>   #define MAS0_ESEL_MASK		0x0FFF0000
>>   #define MAS0_ESEL_SHIFT		16
>>   #define MAS0_ESEL(x)		(((x) << MAS0_ESEL_SHIFT) & MAS0_ESEL_MASK)
>> @@ -86,6 +88,7 @@
>>   #define MAS3_SPSIZE		0x0000003e
>>   #define MAS3_SPSIZE_SHIFT	1
>>   
>> +#define MAS4_TLBSEL_MASK	MAS0_TLBSEL_MASK
>>   #define MAS4_TLBSELD(x) 	MAS0_TLBSEL(x)
>>   #define MAS4_INDD		0x00008000	/* Default IND */
>>   #define MAS4_TSIZED(x)		MAS1_TSIZE(x)
>> diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
>> index dd2cc03..79677d7 100644
>> --- a/arch/powerpc/kvm/e500_mmu_host.c
>> +++ b/arch/powerpc/kvm/e500_mmu_host.c
>> @@ -107,11 +107,15 @@ static u32 get_host_mas0(unsigned long eaddr)
>>   {
>>   	unsigned long flags;
>>   	u32 mas0;
>> +	u32 mas4;
>>   
>>   	local_irq_save(flags);
>>   	mtspr(SPRN_MAS6, 0);
>> +	mas4 = mfspr(SPRN_MAS4);
>> +	mtspr(SPRN_MAS4, mas4 & ~MAS4_TLBSEL_MASK);
>>   	asm volatile("tlbsx 0, %0" : : "b" (eaddr & ~CONFIG_PAGE_OFFSET));
>>   	mas0 = mfspr(SPRN_MAS0);
>> +	mtspr(SPRN_MAS4, mas4);
>>   	local_irq_restore(flags);
>>   
>>   	return mas0;
> Reviewed-by: Scott Wood <scottwood@freescale.com>

Thanks, applied to kvm-ppc-queue.


Alex