Re: [PATCH] dax: Split pmd map when fallback on COW

[Toshi Kani]

On Mon, 2015-11-23 at 13:05 -0700, Toshi Kani wrote:
> An infinite loop of PMD faults was observed when attempted to
> mlock() a private read-only PMD mmap'd range of a DAX file.

Typo: the above description should be (remove "read-only"): 

An infinite loop of PMD faults was observed when attempted to mlock() a private
PMD mmap'd range of a DAX file.

-Toshi

> __dax_pmd_fault() simply returns with VM_FAULT_FALLBACK when
> falling back to PTE on COW.  However, __handle_mm_fault()
> returns without falling back to handle_pte_fault() because
> a PMD map is present in this case.
> 
> Change __dax_pmd_fault() to split the PMD map, if present,
> before returning with VM_FAULT_FALLBACK.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/