linux-kernel - [PATCH -tip] perf_counter/x86: Remove masking and unmasking of LVT error register.

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-next>] [day] [month] [year] [list]

Message-ID: <20090528071655.GA21039@ywang-moblin2.bj.intel.com>
Date:	Thu, 28 May 2009 15:16:55 +0800
From:	Yong Wang <yong.y.wang@...ux.intel.com>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	linux-kernel@...r.kernel.org
Subject: [PATCH -tip] perf_counter/x86: Remove masking and unmasking of LVT
	error register.

Masking and unmasking of LVT error register become unnecessary as NMI mode will be
used all the time.

Signed-off-by: Yong Wang <yong.y.wang@...el.com>

---
 perf_counter.c |    6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index 2eeaa99..444bcf2 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -865,22 +865,16 @@ void set_perf_counter_pending(void)
 
 void perf_counters_lapic_init(int nmi)
 {
-	u32 apic_val;
-
 	if (!x86_pmu_initialized())
 		return;
 
 	/*
 	 * Enable the performance counter vector in the APIC LVT:
 	 */
-	apic_val = apic_read(APIC_LVTERR);
-
-	apic_write(APIC_LVTERR, apic_val | APIC_LVT_MASKED);
 	if (nmi)
 		apic_write(APIC_LVTPC, APIC_DM_NMI);
 	else
 		apic_write(APIC_LVTPC, LOCAL_PERF_VECTOR);
-	apic_write(APIC_LVTERR, apic_val);
 }
 
 static int __kprobes
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/