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| author | Will Deacon <will.deacon@arm.com> | 2015-08-20 12:47:13 +0200 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2015-08-20 17:17:58 +0200 |
| commit | d8d23fa0f27f3b2942a7bbc7378c7735324ed519 (patch) | |
| tree | 2b7dd9735a738778ceb99d5c357a293daf64f4df /arch | |
| parent | arm64: kconfig: Move LIST_POISON to a safe value (diff) | |
| download | linux-d8d23fa0f27f3b2942a7bbc7378c7735324ed519.tar.xz linux-d8d23fa0f27f3b2942a7bbc7378c7735324ed519.zip | |
arm64: mdscr_el1: avoid exposing DCC to userspace
We don't want to expose the DCC to userspace, particularly as there is
a kernel console driver for it.
This patch resets mdscr_el1 to disable userspace access to the DCC
registers on the cold boot path.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/mm/proc.S | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 6e8765a2bddd..e4ee7bd8830a 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -151,7 +151,8 @@ ENTRY(__cpu_setup) mov x0, #3 << 20 msr cpacr_el1, x0 // Enable FP/ASIMD - msr mdscr_el1, xzr // Reset mdscr_el1 + mov x0, #1 << 12 // Reset mdscr_el1 and disable + msr mdscr_el1, x0 // access to the DCC from EL0 /* * Memory region attributes for LPAE: * |