Will Deacon 3eb9cdffb3 Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID" ... This partially reverts commit 16c9afc776. Alex Bee reports a regression in 5.14 on their RK3328 SoC when configuring the PL330 DMA controller: | ------------[ cut here ]------------ | WARNING: CPU: 2 PID: 373 at kernel/dma/mapping.c:235 dma_map_resource+0x68/0xc0 | Modules linked in: spi_rockchip(+) fuse | CPU: 2 PID: 373 Comm: systemd-udevd Not tainted 5.14.0-rc7 #1 | Hardware name: Pine64 Rock64 (DT) | pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) | pc : dma_map_resource+0x68/0xc0 | lr : pl330_prep_slave_fifo+0x78/0xd0 This appears to be because dma_map_resource() is being called for a physical address which does not correspond to a memory address yet does have a valid 'struct page' due to the way in which the vmemmap is constructed. Prior to 16c9afc776 ("arm64/mm: drop HAVE_ARCH_PFN_VALID"), the arm64 implementation of pfn_valid() called memblock_is_memory() to return 'false' for such regions and the DMA mapping request would proceed. However, now that we are using the generic implementation where only the presence of the memory map entry is considered, we return 'true' and erroneously fail with DMA_MAPPING_ERROR because we identify the region as DRAM. Although fixing this in the DMA mapping code is arguably the right fix, it is a risky, cross-architecture change at this stage in the cycle. So just revert arm64 back to its old pfn_valid() implementation for v5.14. The change to the generic pfn_valid() code is preserved from the original patch, so as to avoid impacting other architectures. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Christoph Hellwig <hch@lst.de> Reported-by: Alex Bee <knaerzche@gmail.com> Link: https://lore.kernel.org/r/d3a3c828-b777-faf8-e901-904995688437@gmail.com Signed-off-by: Will Deacon <will@kernel.org>		2021-08-25 11:33:24 +01:00
..
boot	ARM: Devicetree material for 5.14	2021-07-10 09:33:54 -07:00
configs	Additional Qualcomm ARM64 defconfig udpate for v5.14	2021-06-23 19:01:58 -07:00
crypto	crypto: arm64 - use a pattern rule for generating *.S files	2021-05-14 19:07:54 +08:00
include	Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID"	2021-08-25 11:33:24 +01:00
kernel	arm64: stacktrace: avoid tracing arch_stack_walk()	2021-08-03 10:39:35 +01:00
kvm	Merge branch 'akpm' (patches from Andrew)	2021-07-02 12:08:10 -07:00
lib	arm64: Avoid premature usercopy failure	2021-07-15 17:29:14 +01:00
mm	Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID"	2021-08-25 11:33:24 +01:00
net	Networking changes for 5.14.	2021-06-30 15:51:09 -07:00
tools	arm64: Allow mismatched 32-bit EL0 support	2021-06-11 13:25:40 +01:00
xen
Kbuild	bpf: Fix BPF_JIT kconfig symbol dependency	2021-05-20 23:48:37 +02:00
Kconfig	Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID"	2021-08-25 11:33:24 +01:00
Kconfig.debug
Kconfig.platforms	Merge branch 'arm/fixes' into arm/soc	2021-07-09 10:46:02 -07:00
Makefile	arm64: clean vdso & vdso32 files	2021-08-11 11:04:55 +01:00