1a6d80ff24
Pull arm64 fix from Will Deacon:
"We received a report this week that the generic version of
pfn_valid(), which we switched to this merge window in 16c9afc776
("arm64/mm: drop HAVE_ARCH_PFN_VALID"), interacts badly with
dma_map_resource() due to the following check:
/* Don't allow RAM to be mapped */
if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr))))
return DMA_MAPPING_ERROR;
Since the ongoing saga to determine the semantics of pfn_valid() is
unlikely to be resolved this week (does it indicate valid memory, or
just the presence of a struct page, or whether that struct page has
been initialised?), just revert back to our old version of pfn_valid()
for 5.14.
Summary:
- Fix dma_map_resource() by reverting back to old pfn_valid() code"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID"
Linux kernel
============
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