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From: Jan Kiszka <jan.kiszka@siemens.com>
To: Marcelo Tosatti <mtosatti@redhat.com>, Gleb Natapov <gleb@redhat.com>
Cc: qemu-devel <qemu-devel@nongnu.org>, kvm <kvm@vger.kernel.org>
Subject: [PATCH][QEMU] vmxcap: Open MSR file in unbuffered mode
Date: Wed, 13 Feb 2013 12:43:10 +0100	[thread overview]
Message-ID: <511B7C4E.8070403@siemens.com> (raw)

Python may otherwise decide to to read larger chunks, applying the seek
only on the software buffer. This will return results from the wrong
MSRs.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 scripts/kvm/vmxcap |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/kvm/vmxcap b/scripts/kvm/vmxcap
index 0b23f77..6363e73 100755
--- a/scripts/kvm/vmxcap
+++ b/scripts/kvm/vmxcap
@@ -27,9 +27,9 @@ MSR_IA32_VMX_VMFUNC = 0x491
 class msr(object):
     def __init__(self):
         try:
-            self.f = file('/dev/cpu/0/msr')
+            self.f = open('/dev/cpu/0/msr', 'r', 0)
         except:
-            self.f = file('/dev/msr0')
+            self.f = open('/dev/msr0', 'r', 0)
     def read(self, index, default = None):
         import struct
         self.f.seek(index)
-- 
1.7.3.4

             reply	other threads:[~2013-02-13 11:43 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-02-13 11:43 Jan Kiszka [this message]
2013-02-14  7:55 ` [PATCH][QEMU] vmxcap: Open MSR file in unbuffered mode Gleb Natapov
2013-02-14 10:25   ` [Qemu-devel] " Andreas Färber
2013-02-14 12:02     ` Gleb Natapov

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