Re: [Bug 219609] File corruptions on SSD in 1st M.2 socket of AsRock X600M-STX + Ryzen 8700G

[Thorsten Leemhuis]

On 17.01.25 10:55, Christoph Hellwig wrote:
> On Fri, Jan 17, 2025 at 10:51:09AM +0100, Thorsten Leemhuis wrote:
>> By booting with 'ignore_loglevel dyndbg="file drivers/pci/* +p"' I
>> suppose? No, that is not printed (but other debug lines from the pci
>> code are).
>>
>> Side note: that "PCI-DMA: Using software bounce buffering for IO
>>>> (SWIOTLB)" message does show up on two other AMD machines I own as
>> well. One also has a Ryzen 8000, the other one a much older one.
>>
>> And BTW a few bits of the latest development in the bugzilla ticket
>> (https://bugzilla.kernel.org/show_bug.cgi?id=219609 ):
>>
>> * iommu=pt and amd_iommu=off seems to work around the problem (in
>> addition to disabling the iommu in the BIOS setup).
> 
> That suggests the problem is related to the dma-iommu code, and
> my strong suspect is the swiotlb bounce buffering for untrusted
> device.  If you feel adventurous, can you try building a kernel
> where dev_use_swiotlb() in drivers/iommu/dma-iommu.c is hacked
> to always return false?

Tried that, did not help: I still get corrupted data.

Ciao, Thorsten