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| author |   Catalin Marinas <catalin.marinas@arm.com> | 2016-07-01 14:58:21 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2016-11-21 17:33:47 +0000 |
| commit | bd38967d406fb4f9fca67d612db71b5d74cfb0f5 (patch) | |
| tree | fbcc9bd2e2f70c40387fe166de6f4e874c0d0bdb /arch/arm64/kernel/armv8_deprecated.c | |
| parent | arm64: Update the synchronous external abort fault description (diff) | |
| download | linux-dev-bd38967d406fb4f9fca67d612db71b5d74cfb0f5.tar.xz linux-dev-bd38967d406fb4f9fca67d612db71b5d74cfb0f5.zip | |
arm64: Factor out PAN enabling/disabling into separate uaccess_* macros
This patch moves the directly coded alternatives for turning PAN on/off
into separate uaccess_{enable,disable} macros or functions. The asm
macros take a few arguments which will be used in subsequent patches.
Note that any (unlikely) access that the compiler might generate between
uaccess_enable() and uaccess_disable(), other than those explicitly
specified by the user access code, will not be protected by PAN.
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/armv8_deprecated.c')
| -rw-r--r-- | arch/arm64/kernel/armv8_deprecated.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c index b0988bb1bf64..bdb35b92003e 100644 --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -14,7 +14,6 @@ #include <linux/slab.h> #include <linux/sysctl.h> -#include <asm/alternative.h> #include <asm/cpufeature.h> #include <asm/insn.h> #include <asm/opcodes.h> @@ -285,10 +284,10 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table) #define __SWP_LL_SC_LOOPS 4 #define __user_swpX_asm(data, addr, res, temp, temp2, B) \ +do { \ + uaccess_enable(); \ __asm__ __volatile__( \ " mov %w3, %w7\n" \ - ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ "0: ldxr"B" %w2, [%4]\n" \ "1: stxr"B" %w0, %w1, [%4]\n" \ " cbz %w0, 2f\n" \ @@ -306,12 +305,12 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table) " .popsection" \ _ASM_EXTABLE(0b, 4b) \ _ASM_EXTABLE(1b, 4b) \ - ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ : "=&r" (res), "+r" (data), "=&r" (temp), "=&r" (temp2) \ : "r" (addr), "i" (-EAGAIN), "i" (-EFAULT), \ "i" (__SWP_LL_SC_LOOPS) \ - : "memory") + : "memory"); \ + uaccess_disable(); \ +} while (0) #define __user_swp_asm(data, addr, res, temp, temp2) \ __user_swpX_asm(data, addr, res, temp, temp2, "") |