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Bug#406769: linux-image-2.6.18-3-amd64: rdtsc instruction does not serialise on core2 family



Package: linux-image-2.6.18-3-amd64
Version: 2.6.18-8
Severity: critical
Justification: breaks the whole system


Commit from 2.6.18.6 upstream is vitally important for Core 2 family.

Without this TSC drift between cores will result in unpredictable
hard locks and reboots.


commit e4a835d383dc58212a9648ef905cb8087e0c4ab2
Author: Arjan van de Ven <arjan@linux.intel.com>
Date:   Mon Dec 11 21:45:01 2006 +0100

    [PATCH] x86-64: Mark rdtsc as sync only for netburst, not for core2
    
    On the Core2 cpus, the rdtsc instruction is not serializing (as defined
    in the architecture reference since rdtsc exists) and due to the deep
    speculation of these cores, it's possible that you can observe time go
    backwards between cores due to this speculation. Since the kernel
    already deals with this with the SYNC_RDTSC flag, the solution is
    simple, only assume that the instruction is serializing on family 15...
    
    The price one pays for this is a slightly slower gettimeofday (by a
    dozen or two cycles), but that increase is quite small to pay for a
    really-going-forward tsc counter.
    
    Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
    Signed-off-by: Andi Kleen <ak@suse.de>
    [chrisw: backported to 2.6.18]
    Signed-off-by: Chris Wright <chrisw@sous-sol.org>

-- System Information:
Debian Release: 4.0
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.19.2
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)

Versions of packages linux-image-2.6.18-3-amd64 depends on:
ii  coreutil 5.97-5.2                        The GNU core utilities
ii  debconf  1.5.11                          Debian configuration management sy
ii  e2fsprog 1.39+1.40-WIP-2006.11.14+dfsg-1 ext2 file system utilities and lib
ii  initramf 0.85e                           tools for generating an initramfs
ii  module-i 3.3-pre4-1                      tools for managing Linux kernel mo

linux-image-2.6.18-3-amd64 recommends no packages.

-- debconf information:
  shared/kernel-image/really-run-bootloader: true
  linux-image-2.6.18-3-amd64/postinst/old-system-map-link-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/preinst/initrd-2.6.18-3-amd64:
  linux-image-2.6.18-3-amd64/postinst/bootloader-test-error-2.6.18-3-amd64:
  linux-image-2.6.18-3-amd64/postinst/kimage-is-a-directory:
  linux-image-2.6.18-3-amd64/preinst/abort-overwrite-2.6.18-3-amd64:
  linux-image-2.6.18-3-amd64/postinst/depmod-error-initrd-2.6.18-3-amd64: false
  linux-image-2.6.18-3-amd64/preinst/lilo-initrd-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/postinst/bootloader-error-2.6.18-3-amd64:
  linux-image-2.6.18-3-amd64/postinst/old-dir-initrd-link-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/preinst/bootloader-initrd-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/postinst/old-initrd-link-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/preinst/failed-to-move-modules-2.6.18-3-amd64:
  linux-image-2.6.18-3-amd64/preinst/elilo-initrd-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/prerm/removing-running-kernel-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/preinst/overwriting-modules-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/postinst/depmod-error-2.6.18-3-amd64: false
  linux-image-2.6.18-3-amd64/prerm/would-invalidate-boot-loader-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/postinst/create-kimage-link-2.6.18-3-amd64: true
  linux-image-2.6.18-3-amd64/preinst/lilo-has-ramdisk:
  linux-image-2.6.18-3-amd64/preinst/already-running-this-2.6.18-3-amd64:
  linux-image-2.6.18-3-amd64/preinst/abort-install-2.6.18-3-amd64:



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