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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Apr 28, 2020 at 01:58:12PM +0100, Will Deacon wrote: > On Tue, Mar 31, 2020 at 03:44:12PM +0000, George Spelvin wrote: > > get_random_bytes() is approximately 4x the cost of two > > get_random_u64() calls, because the former implements > > anti-backtracking. > > > > Because these are authentication keys, useless to an attacker > > as soon as the kernel stops using them, there is no security > > benefit from anti-backtracking. > > > > Signed-off-by: George Spelvin > > Cc: Mark Rutland > > Cc: Will Deacon > > Cc: Catalin Marinas > > Cc: linux-arm-kernel@lists.infradead.org > > --- > > v2: Took out all the clever bitmap-based stuff and made a simple > > boring helper function to replace get_random_bytes(&key, 16). > > > > arch/arm64/include/asm/pointer_auth.h | 16 +++++++++++----- > > arch/arm64/kernel/pointer_auth.c | 10 +++++----- > > 2 files changed, 16 insertions(+), 10 deletions(-) > > Please can you resend this against the arm64 for-next/ptr-auth branch [1]? > I can't apply it as-is. Any update on this one? Cheers, Will > [1] https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=for-next/ptr-auth _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel