linux-kernel - [039/127] x86: AMD Northbridge: Verify NBs node is online

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: <20101208004428.224683861@clark.site>
Date:	Tue, 07 Dec 2010 16:43:45 -0800
From:	Greg KH <gregkh@...e.de>
To:	linux-kernel@...r.kernel.org, stable@...nel.org
Cc:	stable-review@...nel.org, torvalds@...ux-foundation.org,
	akpm@...ux-foundation.org, alan@...rguk.ukuu.org.uk,
	Prarit Bhargava <prarit@...hat.com>, bhavna.sarathy@....com,
	jbarnes@...tuousgeek.org, andreas.herrmann3@....com,
	Ingo Molnar <mingo@...e.hu>, maximilian attems <max@...o.at>
Subject: [039/127] x86: AMD Northbridge: Verify NBs node is online

2.6.32-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Prarit Bhargava <prarit@...hat.com>

commit 303fc0870f8fbfabe260c5c32b18e53458d597ea upstream.

Fix panic seen on some IBM and HP systems on 2.6.32-rc6:

 BUG: unable to handle kernel NULL pointer dereference at (null)
 IP: [<ffffffff8120bf3f>] find_next_bit+0x77/0x9c
  [...]
  [<ffffffff8120bbde>] cpumask_next_and+0x2e/0x3b
  [<ffffffff81225c62>] pci_device_probe+0x8e/0xf5
  [<ffffffff812b9be6>] ? driver_sysfs_add+0x47/0x6c
  [<ffffffff812b9da5>] driver_probe_device+0xd9/0x1f9
  [<ffffffff812b9f1d>] __driver_attach+0x58/0x7c
  [<ffffffff812b9ec5>] ? __driver_attach+0x0/0x7c
  [<ffffffff812b9298>] bus_for_each_dev+0x54/0x89
  [<ffffffff812b9b4f>] driver_attach+0x19/0x1b
  [<ffffffff812b97ae>] bus_add_driver+0xd3/0x23d
  [<ffffffff812ba1e7>] driver_register+0x98/0x109
  [<ffffffff81225ed0>] __pci_register_driver+0x63/0xd3
  [<ffffffff81072776>] ? up_read+0x26/0x2a
  [<ffffffffa0081000>] ? k8temp_init+0x0/0x20 [k8temp]
  [<ffffffffa008101e>] k8temp_init+0x1e/0x20 [k8temp]
  [<ffffffff8100a073>] do_one_initcall+0x6d/0x185
  [<ffffffff8108d765>] sys_init_module+0xd3/0x236
  [<ffffffff81011ac2>] system_call_fastpath+0x16/0x1b

I put in a printk and commented out the set_dev_node()
call when and got this output:

 quirk_amd_nb_node: current numa_node = 0x0, would set to val & 7 = 0x0
 quirk_amd_nb_node: current numa_node = 0x0, would set to val & 7 = 0x1
 quirk_amd_nb_node: current numa_node = 0x0, would set to val & 7 = 0x2
 quirk_amd_nb_node: current numa_node = 0x0, would set to val & 7 = 0x3

I.e. the issue appears to be that the HW has set val to a valid
value, however, the system is only configured for a single
node -- 0, the others are offline.

Check to see if the node is actually online before setting
the numa node for an AMD northbridge in quirk_amd_nb_node().

Signed-off-by: Prarit Bhargava <prarit@...hat.com>
Cc: bhavna.sarathy@....com
Cc: jbarnes@...tuousgeek.org
Cc: andreas.herrmann3@....com
LKML-Reference: <20091112180933.12532.98685.sendpatchset@...rit.bos.redhat.com>
[ v2: clean up the code and add comments ]
Signed-off-by: Ingo Molnar <mingo@...e.hu>
Cc: maximilian attems <max@...o.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>

---
 arch/x86/kernel/quirks.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/arch/x86/kernel/quirks.c
+++ b/arch/x86/kernel/quirks.c
@@ -512,6 +512,7 @@ static void __init quirk_amd_nb_node(str
 {
 	struct pci_dev *nb_ht;
 	unsigned int devfn;
+	u32 node;
 	u32 val;

 	devfn = PCI_DEVFN(PCI_SLOT(dev->devfn), 0);
@@ -520,7 +521,13 @@ static void __init quirk_amd_nb_node(str
 		return;

 	pci_read_config_dword(nb_ht, 0x60, &val);
-	set_dev_node(&dev->dev, val & 7);
+	node = val & 7;
+	/*
+	 * Some hardware may return an invalid node ID,
+	 * so check it first:
+	 */
+	if (node_online(node))
+		set_dev_node(&dev->dev, node);
 	pci_dev_put(nb_ht);
 }

--
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/