From: Stephen Boyd <sboyd@codeaurora.org>
Date: Wed, 29 Nov 2017 15:39:49 -0800
Subject: arm64: Inform user if software PAN is in use
Git-commit: 894cfd149289c8c9c99211b58a2e3ae7027fff7e
Patch-mainline: v4.16-rc1
References: fate#325862
It isn't entirely obvious if we're using software PAN because we
don't say anything about it in the boot log. But if we're using
hardware PAN we'll print a nice CPU feature message indicating
it. Add a print for software PAN too so we know if it's being
used or not.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
arch/arm64/kernel/cpufeature.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 9f4491d16cfb..a11311397430 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1276,6 +1276,9 @@ static void verify_local_cpu_capabilities(void)
if (system_supports_sve())
verify_sve_features();
+
+ if (system_uses_ttbr0_pan())
+ pr_info("Emulating Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
}
void check_local_cpu_capabilities(void)
--
2.11.0