lkml.org 
[lkml]   [2012]   [Apr]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectFwd: [PATCH -v3 40/47] PCI: Add pci bus removal through /sys/.../pci_bus/.../remove
    From
    adding back the CC list


    ---------- Forwarded message ----------
    From: Yinghai Lu <yhlu.kernel@gmail.com>
    Date: Fri, Apr 6, 2012 at 9:24 AM
    Subject: Re: [PATCH -v3 40/47] PCI: Add pci bus removal through
    /sys/.../pci_bus/.../remove
    To: Bjorn Helgaas <bhelgaas@google.com>


    On Fri, Apr 6, 2012 at 9:07 AM, Bjorn Helgaas <bhelgaas@google.com> wrote:
    > On Fri, Apr 6, 2012 at 10:01 AM, Yinghai Lu <yhlu.kernel@gmail.com> wrote:
    >> On Fri, Apr 6, 2012 at 8:50 AM, Jiang Liu <liuj97@gmail.com> wrote:
    >>> Hi Yinghai,
    >>>        I found many other drivers assume that a pci bus won't disappear if
    >>> the corresponding PCI bridge device still exists. The sysfs interface proposed
    >>> here breaks that assumption and may cause many access-after-free issues.
    >>> So what's the purpose of this interface? Should we remove this interface or
    >>> enhance other drivers to avoid invalid memory access issues?
    >
    > Can you point out some of the specifics about drivers making this
    > assumption?  I'm not thrilled about the idea of removing a pci_bus
    > while the upstream bridge pci_dev still exists either.

    I noticed that too. some hotplug driver link to those child bus
    instead of bridge...
    So have prepared some local patches to handle them.

    >
    >> ok, will make it only show up on root bus.
    >
    > OK.  I'm still interested in the specifics because I don't like the
    > way the pci_bus is exposed, even inside the kernel.  The bus itself is
    > not an active entity, and we can't really do anything with it except
    > by touching a device connected to it.

    I want to keep that to remove root bus that is not added acpi root.

    Yinghai
    [unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream]
    \
     
     \ /
      Last update: 2012-04-06 19:45    [W:0.024 / U:123.072 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site