linux-kernel - [PATCH v7 05/13] perf/x86/intel/pt: Introduce a new function to get capability of Intel PT

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: <1525349323-9938-6-git-send-email-luwei.kang@intel.com>
Date:   Thu,  3 May 2018 20:08:35 +0800
From:   Luwei Kang <luwei.kang@...el.com>
To:     kvm@...r.kernel.org
Cc:     tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
        x86@...nel.org, pbonzini@...hat.com, rkrcmar@...hat.com,
        linux-kernel@...r.kernel.org, joro@...tes.org,
        peterz@...radead.org, chao.p.peng@...ux.intel.com,
        Luwei Kang <luwei.kang@...el.com>
Subject: [PATCH v7 05/13] perf/x86/intel/pt: Introduce a new function to get capability of Intel PT

New function __pt_cap_get() will be invoked in KVM to check
if a specific capability is availiable in KVM guest.
Another function pt_cap_get() can only check the hardware
capabilities but this may different with KVM guest because
some features may not be exposed to guest.

Signed-off-by: Luwei Kang <luwei.kang@...el.com>
---
 arch/x86/events/intel/pt.c      | 10 ++++++++--
 arch/x86/include/asm/intel_pt.h |  2 ++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
index d5819a2..a1fe6ff 100644
--- a/arch/x86/events/intel/pt.c
+++ b/arch/x86/events/intel/pt.c
@@ -76,14 +76,20 @@
 	PT_CAP(psb_periods,		1, CPUID_EBX, 0xffff0000),
 };
 
-u32 pt_cap_get(enum pt_capabilities cap)
+u32 __pt_cap_get(u32 *caps, enum pt_capabilities cap)
 {
 	struct pt_cap_desc *cd = &pt_caps[cap];
-	u32 c = pt_pmu.caps[cd->leaf * PT_CPUID_REGS_NUM + cd->reg];
+	u32 c = caps[cd->leaf * PT_CPUID_REGS_NUM + cd->reg];
 	unsigned int shift = __ffs(cd->mask);
 
 	return (c & cd->mask) >> shift;
 }
+EXPORT_SYMBOL_GPL(__pt_cap_get);
+
+u32 pt_cap_get(enum pt_capabilities cap)
+{
+	return __pt_cap_get(pt_pmu.caps, cap);
+}
 EXPORT_SYMBOL_GPL(pt_cap_get);
 
 static ssize_t pt_cap_show(struct device *cdev,
diff --git a/arch/x86/include/asm/intel_pt.h b/arch/x86/include/asm/intel_pt.h
index 2de4db0..3a4f524 100644
--- a/arch/x86/include/asm/intel_pt.h
+++ b/arch/x86/include/asm/intel_pt.h
@@ -27,9 +27,11 @@ enum pt_capabilities {
 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
 void cpu_emergency_stop_pt(void);
 extern u32 pt_cap_get(enum pt_capabilities cap);
+extern u32 __pt_cap_get(u32 *caps, enum pt_capabilities cap);
 #else
 static inline void cpu_emergency_stop_pt(void) {}
 static inline u32 pt_cap_get(enum pt_capabilities cap) { return 0; }
+static u32 __pt_cap_get(u32 *caps, enum pt_capabilities cap) { return 0; }
 #endif
 
 #endif /* _ASM_X86_INTEL_PT_H */
-- 
1.8.3.1