https://github.com/torvalds/linux
Revision 7f284d3cc96e02468a42e045f77af11e5ff8b095 authored by Frank Arnold on 22 April 2010, 14:06:59 UTC, committed by H. Peter Anvin on 14 May 2010, 18:53:01 UTC
When running a quest kernel on xen we get:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
IP: [<ffffffff8142f2fb>] cpuid4_cache_lookup_regs+0x2ca/0x3df
PGD 0
Oops: 0000 [#1] SMP
last sysfs file:
CPU 0
Modules linked in:

Pid: 0, comm: swapper Tainted: G        W  2.6.34-rc3 #1 /HVM domU
RIP: 0010:[<ffffffff8142f2fb>]  [<ffffffff8142f2fb>] cpuid4_cache_lookup_regs+0x
2ca/0x3df
RSP: 0018:ffff880002203e08  EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000060
RDX: 0000000000000000 RSI: 0000000000000040 RDI: 0000000000000000
RBP: ffff880002203ed8 R08: 00000000000017c0 R09: ffff880002203e38
R10: ffff8800023d5d40 R11: ffffffff81a01e28 R12: ffff880187e6f5c0
R13: ffff880002203e34 R14: ffff880002203e58 R15: ffff880002203e68
FS:  0000000000000000(0000) GS:ffff880002200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000038 CR3: 0000000001a3c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper (pid: 0, threadinfo ffffffff81a00000, task ffffffff81a44020)
Stack:
 ffffffff810d7ecb ffff880002203e20 ffffffff81059140 ffff880002203e30
<0> ffffffff810d7ec9 0000000002203e40 000000000050d140 ffff880002203e70
<0> 0000000002008140 0000000000000086 ffff880040020140 ffffffff81068b8b
Call Trace:
 <IRQ>
 [<ffffffff810d7ecb>] ? sync_supers_timer_fn+0x0/0x1c
 [<ffffffff81059140>] ? mod_timer+0x23/0x25
 [<ffffffff810d7ec9>] ? arm_supers_timer+0x34/0x36
 [<ffffffff81068b8b>] ? hrtimer_get_next_event+0xa7/0xc3
 [<ffffffff81058e85>] ? get_next_timer_interrupt+0x19a/0x20d
 [<ffffffff8142fa23>] get_cpu_leaves+0x5c/0x232
 [<ffffffff8106a7b1>] ? sched_clock_local+0x1c/0x82
 [<ffffffff8106a9a0>] ? sched_clock_tick+0x75/0x7a
 [<ffffffff8107748c>] generic_smp_call_function_single_interrupt+0xae/0xd0
 [<ffffffff8101f6ef>] smp_call_function_single_interrupt+0x18/0x27
 [<ffffffff8100a773>] call_function_single_interrupt+0x13/0x20
 <EOI>
 [<ffffffff8143c468>] ? notifier_call_chain+0x14/0x63
 [<ffffffff810295c6>] ? native_safe_halt+0xc/0xd
 [<ffffffff810114eb>] ? default_idle+0x36/0x53
 [<ffffffff81008c22>] cpu_idle+0xaa/0xe4
 [<ffffffff81423a9a>] rest_init+0x7e/0x80
 [<ffffffff81b10dd2>] start_kernel+0x40e/0x419
 [<ffffffff81b102c8>] x86_64_start_reservations+0xb3/0xb7
 [<ffffffff81b103c4>] x86_64_start_kernel+0xf8/0x107
Code: 14 d5 40 ff ae 81 8b 14 02 31 c0 3b 15 47 1c 8b 00 7d 0e 48 8b 05 36 1c 8b
 00 48 63 d2 48 8b 04 d0 c7 85 5c ff ff ff 00 00 00 00 <8b> 70 38 48 8d 8d 5c ff
 ff ff 48 8b 78 10 ba c4 01 00 00 e8 eb
RIP  [<ffffffff8142f2fb>] cpuid4_cache_lookup_regs+0x2ca/0x3df
 RSP <ffff880002203e08>
CR2: 0000000000000038
---[ end trace a7919e7f17c0a726 ]---

The L3 cache index disable feature of AMD CPUs has to be disabled if the
kernel is running as guest on top of a hypervisor because northbridge
devices are not available to the guest. Currently, this fixes a boot
crash on top of Xen. In the future this will become an issue on KVM as
well.

Check if northbridge devices are present and do not enable the feature
if there are none.

[ hpa: backported to 2.6.34 ]

Signed-off-by: Frank Arnold <frank.arnold@amd.com>
LKML-Reference: <1271945222-5283-3-git-send-email-bp@amd64.org>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
1 parent ade029e
Raw File
Tip revision: 7f284d3cc96e02468a42e045f77af11e5ff8b095 authored by Frank Arnold on 22 April 2010, 14:06:59 UTC
x86, cacheinfo: Turn off L3 cache index disable feature in virtualized environments
Tip revision: 7f284d3
Kconfig
#
# Network configuration
#

menuconfig NET
	bool "Networking support"
	select NLATTR
	---help---
	  Unless you really know what you are doing, you should say Y here.
	  The reason is that some programs need kernel networking support even
	  when running on a stand-alone machine that isn't connected to any
	  other computer.
	  
	  If you are upgrading from an older kernel, you
	  should consider updating your networking tools too because changes
	  in the kernel and the tools often go hand in hand. The tools are
	  contained in the package net-tools, the location and version number
	  of which are given in <file:Documentation/Changes>.

	  For a general introduction to Linux networking, it is highly
	  recommended to read the NET-HOWTO, available from
	  <http://www.tldp.org/docs.html#howto>.

if NET

config WANT_COMPAT_NETLINK_MESSAGES
	bool
	help
	  This option can be selected by other options that need compat
	  netlink messages.

config COMPAT_NETLINK_MESSAGES
	def_bool y
	depends on COMPAT
	depends on WIRELESS_EXT || WANT_COMPAT_NETLINK_MESSAGES
	help
	  This option makes it possible to send different netlink messages
	  to tasks depending on whether the task is a compat task or not. To
	  achieve this, you need to set skb_shinfo(skb)->frag_list to the
	  compat skb before sending the skb, the netlink code will sort out
	  which message to actually pass to the task.

	  Newly written code should NEVER need this option but do
	  compat-independent messages instead!

menu "Networking options"

source "net/packet/Kconfig"
source "net/unix/Kconfig"
source "net/xfrm/Kconfig"
source "net/iucv/Kconfig"

config INET
	bool "TCP/IP networking"
	---help---
	  These are the protocols used on the Internet and on most local
	  Ethernets. It is highly recommended to say Y here (this will enlarge
	  your kernel by about 400 KB), since some programs (e.g. the X window
	  system) use TCP/IP even if your machine is not connected to any
	  other computer. You will get the so-called loopback device which
	  allows you to ping yourself (great fun, that!).

	  For an excellent introduction to Linux networking, please read the
	  Linux Networking HOWTO, available from
	  <http://www.tldp.org/docs.html#howto>.

	  If you say Y here and also to "/proc file system support" and
	  "Sysctl support" below, you can change various aspects of the
	  behavior of the TCP/IP code by writing to the (virtual) files in
	  /proc/sys/net/ipv4/*; the options are explained in the file
	  <file:Documentation/networking/ip-sysctl.txt>.

	  Short answer: say Y.

if INET
source "net/ipv4/Kconfig"
source "net/ipv6/Kconfig"
source "net/netlabel/Kconfig"

endif # if INET

config NETWORK_SECMARK
	bool "Security Marking"
	help
	  This enables security marking of network packets, similar
	  to nfmark, but designated for security purposes.
	  If you are unsure how to answer this question, answer N.

menuconfig NETFILTER
	bool "Network packet filtering framework (Netfilter)"
	---help---
	  Netfilter is a framework for filtering and mangling network packets
	  that pass through your Linux box.

	  The most common use of packet filtering is to run your Linux box as
	  a firewall protecting a local network from the Internet. The type of
	  firewall provided by this kernel support is called a "packet
	  filter", which means that it can reject individual network packets
	  based on type, source, destination etc. The other kind of firewall,
	  a "proxy-based" one, is more secure but more intrusive and more
	  bothersome to set up; it inspects the network traffic much more
	  closely, modifies it and has knowledge about the higher level
	  protocols, which a packet filter lacks. Moreover, proxy-based
	  firewalls often require changes to the programs running on the local
	  clients. Proxy-based firewalls don't need support by the kernel, but
	  they are often combined with a packet filter, which only works if
	  you say Y here.

	  You should also say Y here if you intend to use your Linux box as
	  the gateway to the Internet for a local network of machines without
	  globally valid IP addresses. This is called "masquerading": if one
	  of the computers on your local network wants to send something to
	  the outside, your box can "masquerade" as that computer, i.e. it
	  forwards the traffic to the intended outside destination, but
	  modifies the packets to make it look like they came from the
	  firewall box itself. It works both ways: if the outside host
	  replies, the Linux box will silently forward the traffic to the
	  correct local computer. This way, the computers on your local net
	  are completely invisible to the outside world, even though they can
	  reach the outside and can receive replies. It is even possible to
	  run globally visible servers from within a masqueraded local network
	  using a mechanism called portforwarding. Masquerading is also often
	  called NAT (Network Address Translation).

	  Another use of Netfilter is in transparent proxying: if a machine on
	  the local network tries to connect to an outside host, your Linux
	  box can transparently forward the traffic to a local server,
	  typically a caching proxy server.

	  Yet another use of Netfilter is building a bridging firewall. Using
	  a bridge with Network packet filtering enabled makes iptables "see"
	  the bridged traffic. For filtering on the lower network and Ethernet
	  protocols over the bridge, use ebtables (under bridge netfilter
	  configuration).

	  Various modules exist for netfilter which replace the previous
	  masquerading (ipmasqadm), packet filtering (ipchains), transparent
	  proxying, and portforwarding mechanisms. Please see
	  <file:Documentation/Changes> under "iptables" for the location of
	  these packages.

if NETFILTER

config NETFILTER_DEBUG
	bool "Network packet filtering debugging"
	depends on NETFILTER
	help
	  You can say Y here if you want to get additional messages useful in
	  debugging the netfilter code.

config NETFILTER_ADVANCED
	bool "Advanced netfilter configuration"
	depends on NETFILTER
	default y
	help
	  If you say Y here you can select between all the netfilter modules.
	  If you say N the more unusual ones will not be shown and the
	  basic ones needed by most people will default to 'M'.

	  If unsure, say Y.

config BRIDGE_NETFILTER
	bool "Bridged IP/ARP packets filtering"
	depends on BRIDGE && NETFILTER && INET
	depends on NETFILTER_ADVANCED
	default y
	---help---
	  Enabling this option will let arptables resp. iptables see bridged
	  ARP resp. IP traffic. If you want a bridging firewall, you probably
	  want this option enabled.
	  Enabling or disabling this option doesn't enable or disable
	  ebtables.

	  If unsure, say N.

source "net/netfilter/Kconfig"
source "net/ipv4/netfilter/Kconfig"
source "net/ipv6/netfilter/Kconfig"
source "net/decnet/netfilter/Kconfig"
source "net/bridge/netfilter/Kconfig"

endif

source "net/dccp/Kconfig"
source "net/sctp/Kconfig"
source "net/rds/Kconfig"
source "net/tipc/Kconfig"
source "net/atm/Kconfig"
source "net/802/Kconfig"
source "net/bridge/Kconfig"
source "net/dsa/Kconfig"
source "net/8021q/Kconfig"
source "net/decnet/Kconfig"
source "net/llc/Kconfig"
source "net/ipx/Kconfig"
source "drivers/net/appletalk/Kconfig"
source "net/x25/Kconfig"
source "net/lapb/Kconfig"
source "net/econet/Kconfig"
source "net/wanrouter/Kconfig"
source "net/phonet/Kconfig"
source "net/ieee802154/Kconfig"
source "net/sched/Kconfig"
source "net/dcb/Kconfig"

menu "Network testing"

config NET_PKTGEN
	tristate "Packet Generator (USE WITH CAUTION)"
	depends on PROC_FS
	---help---
	  This module will inject preconfigured packets, at a configurable
	  rate, out of a given interface.  It is used for network interface
	  stress testing and performance analysis.  If you don't understand
	  what was just said, you don't need it: say N.

	  Documentation on how to use the packet generator can be found
	  at <file:Documentation/networking/pktgen.txt>.

	  To compile this code as a module, choose M here: the
	  module will be called pktgen.

config NET_TCPPROBE
	tristate "TCP connection probing"
	depends on INET && EXPERIMENTAL && PROC_FS && KPROBES
	---help---
	This module allows for capturing the changes to TCP connection
	state in response to incoming packets. It is used for debugging
	TCP congestion avoidance modules. If you don't understand
	what was just said, you don't need it: say N.

	Documentation on how to use TCP connection probing can be found
	at http://linux-net.osdl.org/index.php/TcpProbe

	To compile this code as a module, choose M here: the
	module will be called tcp_probe.

config NET_DROP_MONITOR
	boolean "Network packet drop alerting service"
	depends on INET && EXPERIMENTAL && TRACEPOINTS
	---help---
	This feature provides an alerting service to userspace in the
	event that packets are discarded in the network stack.  Alerts
	are broadcast via netlink socket to any listening user space
	process.  If you don't need network drop alerts, or if you are ok
	just checking the various proc files and other utilities for
	drop statistics, say N here.

endmenu

endmenu

source "net/ax25/Kconfig"
source "net/can/Kconfig"
source "net/irda/Kconfig"
source "net/bluetooth/Kconfig"
source "net/rxrpc/Kconfig"

config FIB_RULES
	bool

menuconfig WIRELESS
	bool "Wireless"
	depends on !S390
	default y

if WIRELESS

source "net/wireless/Kconfig"
source "net/mac80211/Kconfig"

endif # WIRELESS

source "net/wimax/Kconfig"

source "net/rfkill/Kconfig"
source "net/9p/Kconfig"

endif   # if NET
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