| Message ID | 1456505834-8638-3-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Fri, Feb 26, 2016 at 05:57:14PM +0100, Ard Biesheuvel wrote: > Commit c031a4213c11 ("arm64: kaslr: randomize the linear region") > implements randomization of the linear region, by subtracting a random > multiple of PUD_SIZE from memstart_addr. This causes the virtual mapping > of system RAM to move upwards in the linear region, and at the same time > causes memstart_addr to assume a value which may be negative if the offset > of system RAM in the physical space is smaller than its offset relative to > PAGE_OFFSET in the virtual space. > > Since memstart_addr is effectively an offset now, redefine its type as s64 > so that expressions involving shifting or division preserve its sign. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Applied. Thanks. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 5f8667a99e41..12f8a00fb3f1 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -135,7 +135,7 @@ #include <linux/bitops.h> #include <linux/mmdebug.h> -extern phys_addr_t memstart_addr; +extern s64 memstart_addr; /* PHYS_OFFSET - the physical address of the start of memory. */ #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; }) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 4ea7efc28e65..a2977d33e0dc 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -54,7 +54,7 @@ * executes, which assigns it its actual value. So use a default value * that cannot be mistaken for a real physical address. */ -phys_addr_t memstart_addr __read_mostly = ~0ULL; +s64 memstart_addr __read_mostly = -1; phys_addr_t arm64_dma_phys_limit __read_mostly; #ifdef CONFIG_BLK_DEV_INITRD
Commit c031a4213c11 ("arm64: kaslr: randomize the linear region") implements randomization of the linear region, by subtracting a random multiple of PUD_SIZE from memstart_addr. This causes the virtual mapping of system RAM to move upwards in the linear region, and at the same time causes memstart_addr to assume a value which may be negative if the offset of system RAM in the physical space is smaller than its offset relative to PAGE_OFFSET in the virtual space. Since memstart_addr is effectively an offset now, redefine its type as s64 so that expressions involving shifting or division preserve its sign. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- arch/arm64/include/asm/memory.h | 2 +- arch/arm64/mm/init.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) -- 2.5.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel