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author | Florian Fainelli <f.fainelli@gmail.com> | 2022-07-19 19:33:21 +0300 |
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committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-07-27 19:55:01 +0300 |
commit | fb0fd3469ead5b937293c213daa1f589b4b7ce46 (patch) | |
tree | 92382cedc981a203680589e7d5d69c18a5315ce3 /arch/arm | |
parent | 29589ca09a74cfc0c50ad002e298bf4b8e69e0bd (diff) | |
download | linux-fb0fd3469ead5b937293c213daa1f589b4b7ce46.tar.xz |
ARM: 9216/1: Fix MAX_DMA_ADDRESS overflow
Commit 26f09e9b3a06 ("mm/memblock: add memblock memory allocation apis")
added a check to determine whether arm_dma_zone_size is exceeding the
amount of kernel virtual address space available between the upper 4GB
virtual address limit and PAGE_OFFSET in order to provide a suitable
definition of MAX_DMA_ADDRESS that should fit within the 32-bit virtual
address space. The quantity used for comparison was off by a missing
trailing 0, leading to MAX_DMA_ADDRESS to be overflowing a 32-bit
quantity.
This was caught thanks to CONFIG_DEBUG_VIRTUAL on the bcm2711 platform
where we define a dma_zone_size of 1GB and we have a PAGE_OFFSET value
of 0xc000_0000 (CONFIG_VMSPLIT_3G) leading to MAX_DMA_ADDRESS being
0x1_0000_0000 which overflows the unsigned long type used throughout
__pa() and then __virt_addr_valid(). Because the virtual address passed
to __virt_addr_valid() would now be 0, the function would loudly warn
and flood the kernel log, thus making the platform unable to boot
properly.
Fixes: 26f09e9b3a06 ("mm/memblock: add memblock memory allocation apis")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/include/asm/dma.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm/include/asm/dma.h b/arch/arm/include/asm/dma.h index a81dda65c576..45180a2cc47c 100644 --- a/arch/arm/include/asm/dma.h +++ b/arch/arm/include/asm/dma.h @@ -10,7 +10,7 @@ #else #define MAX_DMA_ADDRESS ({ \ extern phys_addr_t arm_dma_zone_size; \ - arm_dma_zone_size && arm_dma_zone_size < (0x10000000 - PAGE_OFFSET) ? \ + arm_dma_zone_size && arm_dma_zone_size < (0x100000000ULL - PAGE_OFFSET) ? \ (PAGE_OFFSET + arm_dma_zone_size) : 0xffffffffUL; }) #endif |