Hi Peng, sorry for the inconvenience, this is most probably related to these changes: https://lore.kernel.org/linux-arm-kernel/[email protected]/
On Thu, 2020-12-17 at 16:08 +0800, Peng Fan (OSS) wrote: > From: Peng Fan <[email protected]> > > ZONE_DMA should not be disabled, otherwise arm64_dma_phys_limit is > left uninitialized and cause swiotlb have IO TLB above 4GB which > might crash some platforms > > Signed-off-by: Peng Fan <[email protected]> > --- > > Not sure whether need to address code to initialize the variables or > force select ZONE_DMA What is the cause for the swiotlb related crashes? I assume it's DMA into an address too high for the bus, but it might be something else. I figure you have a setup with ZONE_DMA32, ZONE_NORMAL and !ZONE_DMA. First of all, I'd suggest you try arm64's defaults (all zones enabled), the series I mention above should fix most of the issues we've had with ZONE_DMA/ZONE_DMA32 in the past. We now parse DT/ACPI and only create two distinct DMA zones if really needed. Otherwise ZONE_DMA spans the whole 32 bit address space. That said, IMO we're not doing the right thing in the !ZONE_DMA && ZONE_DMA32 case, and this should fix it (I didn't test it): - #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1) + #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit ? : arm64_dma32_phys_limit) Regards, Nicolas
signature.asc
Description: This is a digitally signed message part
