linux-kernel - [PATCH V5 6/6] x86/intel_rdt: Re-enable pseudo-lock measurements

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <bfb9fc31692e0c62d9ca39062e55eceb6a0635b5.1537377064.git.reinette.chatre@intel.com>
Date:   Wed, 19 Sep 2018 10:29:11 -0700
From:   Reinette Chatre <reinette.chatre@...el.com>
To:     tglx@...utronix.de, fenghua.yu@...el.com, tony.luck@...el.com,
        peterz@...radead.org, mingo@...hat.com, acme@...nel.org
Cc:     gavin.hindman@...el.com, jithu.joseph@...el.com,
        dave.hansen@...el.com, hpa@...or.com, x86@...nel.org,
        linux-kernel@...r.kernel.org,
        Reinette Chatre <reinette.chatre@...el.com>
Subject: [PATCH V5 6/6] x86/intel_rdt: Re-enable pseudo-lock measurements

Commit 4a7a54a55e72 ("x86/intel_rdt: Disable PMU access") disabled
measurements of pseudo-locked regions because of incorrect usage
of the performance monitoring hardware.

Cache pseudo-locking measurements are now done correctly with the
in-kernel perf API and its use can be re-enabled at this time.

The adjustment to the in-kernel perf API also separated the L2 and L3
measurements that can be triggered separately from user space. The
re-enabling of the measurements is thus not a simple revert of the
original disable in order to accommodate the additional parameter
possible.

Signed-off-by: Reinette Chatre <reinette.chatre@...el.com>
---
 arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
index c35b975e3b1e..edf30c94c226 100644
--- a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
+++ b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
@@ -1237,7 +1237,7 @@ static ssize_t pseudo_lock_measure_trigger(struct file *file,
 	buf[buf_size] = '\0';
 	ret = kstrtoint(buf, 10, &sel);
 	if (ret == 0) {
-		if (sel != 1)
+		if (sel != 1 && sel != 2 && sel != 3)
 			return -EINVAL;
 		ret = debugfs_file_get(file->f_path.dentry);
 		if (ret)
-- 
2.17.0