forked from luck/tmp_suning_uos_patched
0b2c2a71e6
pci_call_probe() can called recursively when a physcial function is probed and the probing creates virtual functions, which are populated via pci_bus_add_device() which in turn can end up calling pci_call_probe() again. The code has an interesting way to prevent recursing into the workqueue code. That's accomplished by a check whether the current task runs already on the numa node which is associated with the device. While that works to prevent the recursion into the workqueue code, it's racy versus normal execution as there is no guarantee that the node does not vanish after the check. There is another issue with this code. It dereferences cpumask_of_node() unconditionally without checking whether the node is available. Make the detection reliable by: - Mark a probed device as 'is_probed' in pci_call_probe() - Check in pci_call_probe for a virtual function. If it's a virtual function and the associated physical function device is marked 'is_probed' then this is a recursive call, so the call can be invoked in the calling context. - Add a check whether the node is online before dereferencing it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-pci@vger.kernel.org Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170524081548.771457199@linutronix.de |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.