| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.19 120/306] RISC-V: Avoid corrupting the upper 32-bit of phys_addr_t in ioremap | Date | Wed, 27 Nov 2019 21:29:30 +0100 |
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From: Vincent Chen <vincentc@andestech.com>
[ Upstream commit 827a438156e4c423b6875a092e272933952a2910 ]
For 32bit, the upper 32-bit of phys_addr_t will be flushed to zero after AND with PAGE_MASK because the data type of PAGE_MASK is unsigned long. To fix this problem, the page alignment is done by subtracting the page offset instead of AND with PAGE_MASK.
Signed-off-by: Vincent Chen <vincentc@andestech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/riscv/mm/ioremap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/mm/ioremap.c b/arch/riscv/mm/ioremap.c index 70ef2724cdf61..bd2f2db557cc5 100644 --- a/arch/riscv/mm/ioremap.c +++ b/arch/riscv/mm/ioremap.c @@ -42,7 +42,7 @@ static void __iomem *__ioremap_caller(phys_addr_t addr, size_t size, /* Page-align mappings */ offset = addr & (~PAGE_MASK); - addr &= PAGE_MASK; + addr -= offset; size = PAGE_ALIGN(size + offset); area = get_vm_area_caller(size, VM_IOREMAP, caller); -- 2.20.1
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