From: Jiang Liu <liuj97@gmail.com>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>,
Jesse Barnes <jbarnes@virtuousgeek.org>, x86 <x86@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
Randy Dunlap <rdunlap@xenotime.net>,
linux-doc@vger.kernel.org
Subject: Re: [PATCH -v3 40/47] PCI: Add pci bus removal through /sys/.../pci_bus/.../remove
Date: Sat, 07 Apr 2012 00:22:34 +0800 [thread overview]
Message-ID: <4F7F184A.3080001@gmail.com> (raw)
In-Reply-To: <CAErSpo6gitMTVXeMBOSJFRHvQT_iJ-RGmLduYsGEM+3YAPE2CQ@mail.gmail.com>
On 04/07/2012 12:07 AM, Bjorn Helgaas 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.
According to my understanding, following drivers may have such an assumption:
acpiphp, pciehp, shpcphp, acpi/pci_slot, acpi/pci_bind.
I suspect there are still other drivers have such issues.
>
>> 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.
>
> Bjorn
next prev parent reply other threads:[~2012-04-06 16:22 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-19 5:45 [PATCH 00/47] PCI, x86: pci root bus hotplug support Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 02/47] PNPACPI: Fix device ref leaking in acpi_pnp_match Yinghai Lu
[not found] ` <1332135996-13860-1-git-send-email-yinghai-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2012-03-19 5:45 ` [PATCH -v3 01/47] IOMMU: Update dmar units devices list during hotplug Yinghai Lu
2012-03-19 5:45 ` Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 03/47] IOMMU: Fix tboot force iommu logic Yinghai Lu
2012-03-19 5:45 ` Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 04/47] x86, PCI: Fix non acpi path pci_sysdata leaking with release_fn Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 05/47] PCI: Separate out pci_assign_unassigned_bus_resources() Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 06/47] PCI: Move back pci_rescan_bus() Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 07/47] PCI: pci_bus_size_bridges() should not size own bridge Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 08/47] PCI: Use __pci_bus_size_bridges() directly in pci_assign_unassigned_bus_resources() Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 09/47] PCI, sysfs: Use device_type and attr_groups with pci dev Yinghai Lu
2012-03-19 5:45 ` [PATCH -v3 10/47] PCI, sysfs: create rescan_bridge under /sys/.../pci/devices/... for pci bridges Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 11/47] PCI: Add pci_bus_add_single_device() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 12/47] PCI: Make pci_rescan_bus_bridge_resize() use pci_scan_bridge instead Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 13/47] PCI: Clean up rescan_bus_bridge_resize() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 14/47] PCI: Rescan bus or bridge using callback method too Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 15/47] PCI, sysfs: Clean up rescan/remove with scheule_callback Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 16/47] x86, PCI: Separate pcibios_allocate_bridge_resources() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 17/47] x86, PCI: Separate pcibios_allocate_dev_resources() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 18/47] x86, PCI: Let pcibios_allocate_bus_resources() take bus instead Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 19/47] PCI: Claim hw/fw allocated resources in hot add path Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 20/47] Correctly clean up pci root buses in function pci_remove_bus() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 21/47] PCI: Move pci_stop_and_remove_behind_bridge() down Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 22/47] PCI: Add __pci_remove_bus_devices() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 23/47] PCI: Use list_for_each_entry_safe instead of list_for_each_safe Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 24/47] PCI: Add pci_stop_and_remove_bus() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 25/47] Fix an access-after-free issue in function pci_stop_and_remove_bus() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 26/47] PCI, ACPI: Make acpi_pci_root_remove remove pci root bus too Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 27/47] PCI, acpiphp: Separate out hot-add support of pci host bridge Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 28/47] PCI, ACPI: Add pci_root_hp hot removal notification support Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 29/47] PCI, ACPI: Add alloc_acpi_hp_work() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 30/47] PCI, acpiphp: Use acpi_hp_work Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 31/47] PCI, pci_root_hp: " Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 32/47] PCI, ACPI: Make kacpi_hotplug_wq static Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 33/47] PCI: Add debug print out for pci related dev release Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 34/47] PCI, pciehp: Separate pci_hp_add_bridge() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 35/47] PCI, cphi_hotplug: Simplify configure_slot Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 36/47] PCI, shpchp: Simplify configure_device Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 37/47] PCI: Kill pci_is_reassignedev() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 38/47] PCI, sysfs: Prepare to kill pci device rescan Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 39/47] ACPI: Enable SCI_EMULATE to manually simulate physical hotplug testing Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 40/47] PCI: Add pci bus removal through /sys/.../pci_bus/.../remove Yinghai Lu
2012-04-06 15:50 ` Jiang Liu
2012-04-06 16:01 ` Yinghai Lu
2012-04-06 16:07 ` Bjorn Helgaas
2012-04-06 16:22 ` Jiang Liu [this message]
[not found] ` <CAE9FiQUjsiEvGGZz4sPux5AM7ipDsqgqgh5bh2QA7GJVBTqDKw@mail.gmail.com>
2012-04-06 17:42 ` Fwd: " Yinghai Lu
2012-04-06 18:05 ` Bjorn Helgaas
2012-04-06 18:11 ` Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 41/47] PCI, ACPI: Add acpi_pci_root_rescan() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 42/47] PCI: Add __pci_scan_root_bus() that can skip bus_add Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 43/47] x86, PCI: add __pci_scan_root_bus_on_node() " Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 44/47] x86, PCI: add __pcibios_scan_specific_bus " Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 45/47] x86, PCI: Add pcibios_root_rescan() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 46/47] x86, PCI: Add arch version pci_root_rescan() Yinghai Lu
2012-03-19 5:46 ` [PATCH -v3 47/47] PCI: Add /sys/bus/pci/rescan_root Yinghai Lu
2012-03-19 21:37 ` [PATCH 00/47] PCI, x86: pci root bus hotplug support Bjorn Helgaas
2012-03-20 17:20 ` Yinghai Lu
2012-03-30 18:27 ` Yinghai Lu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4F7F184A.3080001@gmail.com \
--to=liuj97@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=bhelgaas@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=jbarnes@virtuousgeek.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=rdunlap@xenotime.net \
--cc=torvalds@linux-foundation.org \
--cc=x86@kernel.org \
--cc=yhlu.kernel@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.