Re: [PATCH v7u1 26/31] x86: Don't enable swiotlb if there is notenough ram for it

From: Shuah Khan
Date: Sat Jan 05 2013 - 17:05:05 EST

On Fri, Jan 4, 2013 at 9:10 PM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
> On Fri, Jan 4, 2013 at 6:02 PM, Shuah Khan <shuahkhan@xxxxxxxxx> wrote:
>> I applied your patch to 3.6.11 and changed the panic() to pr_info()
>> and also changed enough_mem_for_swiotlb() to always return false to
>> simulate not enough memory condition as this system does have enough
>> memory.
>> So at least on this AMD system, your patch will result in a panic.
> ok, thanks for testing.
> if enough_mem_for_swiotlb() return false really, allocating buffer
> for swiotlb with bootmem would panic already, right?
> so this patch just delay the panic a while for AMD system with
> unhandled devices by IOMMU.
> Thanks
> Yinghai

Right. It will eventually panic. I think this is not a valid test. I
am planning to run more tests without forcing no memory condition
which is what I should have done in the first place. I will let you
know what I find, very likely Monday.

-- Shuah
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