From: Huang Ying <ying.huang@intel.com>
To: Jiang Liu <liuj97@gmail.com>
Cc: Yijing Wang <wangyijing@huawei.com>,
Bjorn Helgaas <bhelgaas@google.com>,
Rusty Russell <rusty@rustcorp.com.au>,
Mauro Carvalho Chehab <mchehab@redhat.com>,
PCI <linux-pci@vger.kernel.org>,
Hanjun Guo <guohanjun@huawei.com>,
linux-kernel@vger.kernel.org
Subject: Re: [RESEND BUGFIX PATCH 1/3] PCI/AER: fix pci_ops return NULL when hotplug a pci bus which was doing aer error inject
Date: Tue, 28 Aug 2012 08:38:24 +0800 [thread overview]
Message-ID: <1346114304.6279.341.camel@yhuang-dev> (raw)
In-Reply-To: <503B8CD4.8070802@gmail.com>
On Mon, 2012-08-27 at 23:05 +0800, Jiang Liu wrote:
> Is it ok to ignore such a case? After all, aer_inject is just a test tool:)
> It's not worth to change the core logic for such a corner case.
> --Gerry
Why ignore? At least you can prevent aer_inject from unload if
something special happened.
Best Regards,
Huang Ying
> On 08/27/2012 09:23 AM, Huang Ying wrote:
> > On Sat, 2012-08-25 at 17:59 +0800, Yijing Wang wrote:
> >> When we inject aer errors to the target pci device by aer_inject module, the pci_ops of pci
> >> bus which the target device is on will be assign to pci_ops_aer.So if the target pci device
> >> is a bridge, once we hotplug the pci bus(child bus) which the target device bridges to, child
> >> bus's pci_ops will be assigned to pci_ops_aer too.Now every access to the child bus's device
> >> will result to system panic, because it return NULL pci_ops in pci_read_aer.
> >> This patch fix this.
> >>
> >> CallTrace:
> >> bash[5908]: NaT consumption 17179869216 [1]
> >> Modules linked in: aer_inject cpufreq_conservative cpufreq_userspace cpufreq_pow
> >> ersave acpi_cpufreq binfmt_misc fuse nls_iso8859_1 loop ipmi_si(+) ipmi_devintf
> >> ipmi_msghandler dm_mod ppdev iTCO_wdt iTCO_vendor_support sg igb parport_pc i2c_
> >> i801 mptctl i2c_core serio_raw hid_generic lpc_ich mfd_core parport button conta
> >> iner usbhid hid uhci_hcd ehci_hcd usbcore usb_common sd_mod crc_t10dif ext3 mbca
> >> che jbd fan processor ide_pci_generic ide_core ata_piix libata mptsas mptscsih m
> >> ptbase scsi_transport_sas scsi_mod thermal thermal_sys hwmon
> >>
> >> Pid: 5908, CPU 9, comm: bash
> >> psr : 00001010085a2010 ifs : 800000000000048e ip : [<a000000220b815b0>] Not
> >> tainted (3.5.0-rc6yijing-repo)
> >> ip is at pci_read_aer+0x330/0x460 [aer_inject]
> >> unat: 0000000000000000 pfs : 000000000000048e rsc : 0000000000000003
> >> rnat: 0000000000000000 bsps: 0000000000000000 pr : 65519aa6a6969aa5
> >> ldrs: 0000000000000000 ccv : ffffffff00000001 fpsr: 0009804c8a70033f
> >> csd : 0000000000000000 ssd : 0000000000000000
> >> b0 : a000000220b815b0 b6 : a000000220b81280 b7 : a0000001006d56a0
> >> f6 : 1003e0000000000000005 f7 : 1003e0000000000000028
> >> f8 : 1003e00000000000000c8 f9 : 1003e0000000000000005
> >> f10 : 1003e627ec1e2f4c0d8a7 f11 : 1003e0000000000000011
> >> r1 : a0000001014e63c0 r2 : 0000000000000738 r3 : 000000000000fffe
> >> r8 : 0000000000000736 r9 : 0000000000000042 r10 : e000001f08f4c898
> >> r11 : 0000000000000000 r12 : e000000f3dfcfdc0 r13 : e000000f3dfc0000
> >> r14 : 0000000000000738 r15 : 0000000000004000 r16 : a000000220b827c8
> >> r17 : a000000220b827b8 r18 : ffffffffffffff00 r19 : e000000f073b0110
> >> r20 : 0000000000000042 r21 : e000000f073b0114 r22 : 0000000000000000
> >> r23 : e000000f073b0118 r24 : a0000001009e0e49 r25 : 0000000000000001
> >> r26 : 0000000000007041 r27 : e000000f3dfcfde0 r28 : 0000000000000000
> >> r29 : e000000f3dfcfc08 r30 : a000000220b827c8 r31 : e000001f074d6000
> >>
> >> Call Trace:
> >> [<a000000100016500>] show_stack+0x80/0xa0
> >> sp=e000000f3dfcf800 bsp=e000000f3dfc1758
> >> [<a000000100016b60>] show_regs+0x640/0x920
> >> sp=e000000f3dfcf9d0 bsp=e000000f3dfc1700
> >> [<a000000100040770>] die+0x190/0x2c0
> >> sp=e000000f3dfcf9e0 bsp=e000000f3dfc16c0
> >> [<a0000001000408f0>] die_if_kernel+0x50/0x80
> >> sp=e000000f3dfcf9e0 bsp=e000000f3dfc1690
> >> [<a000000100903a90>] ia64_fault+0xf0/0x15e0
> >> sp=e000000f3dfcf9e0 bsp=e000000f3dfc1640
> >> [<a00000010000c0a0>] ia64_native_leave_kernel+0x0/0x270
> >> sp=e000000f3dfcfbf0 bsp=e000000f3dfc1640
> >> [<a000000220b815b0>] pci_read_aer+0x330/0x460 [aer_inject]
> >> sp=e000000f3dfcfdc0 bsp=e000000f3dfc15c8
> >> [<a0000001004ace00>] pci_bus_read_config_dword+0xe0/0x140
> >> sp=e000000f3dfcfdc0 bsp=e000000f3dfc1580
> >> [<a0000001004b0c10>] pci_bus_read_dev_vendor_id+0x50/0x200
> >> sp=e000000f3dfcfdd0 bsp=e000000f3dfc1530
> >> [<a0000001008d3d10>] pci_scan_single_device+0x90/0x200
> >> sp=e000000f3dfcfdd0 bsp=e000000f3dfc14f8
> >> [<a0000001004b24b0>] pci_scan_slot+0xb0/0x320
> >> sp=e000000f3dfcfde0 bsp=e000000f3dfc14a8
> >> [<a0000001008d9e90>] pci_scan_child_bus+0x90/0x2e0
> >> sp=e000000f3dfcfde0 bsp=e000000f3dfc1468
> >> [<a0000001008d9580>] pci_scan_bridge+0x540/0xdc0
> >> sp=e000000f3dfcfde0 bsp=e000000f3dfc13d0
> >> [<a0000001008da0b0>] pci_scan_child_bus+0x2b0/0x2e0
> >> sp=e000000f3dfcfe00 bsp=e000000f3dfc1390
> >> [<a0000001008d5bd0>] pci_rescan_bus+0x50/0x220
> >> sp=e000000f3dfcfe00 bsp=e000000f3dfc1358
> >> [<a0000001004c2ab0>] bus_rescan_store+0xf0/0x160
> >> sp=e000000f3dfcfe10 bsp=e000000f3dfc1328
> >> [<a0000001006110b0>] bus_attr_store+0x70/0xa0
> >> sp=e000000f3dfcfe20 bsp=e000000f3dfc12f0
> >> [<a000000100343b00>] sysfs_write_file+0x240/0x340
> >> sp=e000000f3dfcfe20 bsp=e000000f3dfc1298
> >> [<a00000010025e230>] vfs_write+0x1b0/0x3a0
> >> sp=e000000f3dfcfe20 bsp=e000000f3dfc1250
> >> [<a00000010025e5e0>] sys_write+0x80/0x100
> >> sp=e000000f3dfcfe20 bsp=e000000f3dfc11d0
> >> [<a00000010000bf20>] ia64_ret_from_syscall+0x0/0x20
> >> sp=e000000f3dfcfe30 bsp=e000000f3dfc11d0
> >> [<a000000000040720>] __kernel_syscall_via_break+0x0/0x20
> >> sp=e000000f3dfd0000 bsp=e000000f3dfc11d0
> >> Disabling lock debugging due to kernel taint
> >>
> >> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
> >> Signed-off-by: Jiang Liu <liuj97@gmail.com>
> >> ---
> >> drivers/pci/pcie/aer/aer_inject.c | 21 +++++++++++++++++++++
> >> 1 files changed, 21 insertions(+), 0 deletions(-)
> >>
> >> diff --git a/drivers/pci/pcie/aer/aer_inject.c b/drivers/pci/pcie/aer/aer_inject.c
> >> index 5222986..fc28785 100644
> >> --- a/drivers/pci/pcie/aer/aer_inject.c
> >> +++ b/drivers/pci/pcie/aer/aer_inject.c
> >> @@ -109,6 +109,19 @@ static struct aer_error *__find_aer_error_by_dev(struct pci_dev *dev)
> >> return __find_aer_error((u16)domain, dev->bus->number, dev->devfn);
> >> }
> >>
> >> +static bool pci_is_upstream_bus(struct pci_bus *bus, struct pci_bus *up_bus)
> >> +{
> >> + struct pci_bus *pbus = bus->parent;
> >> +
> >> + while (pbus) {
> >> + if (pbus == up_bus)
> >> + return true;
> >> + pbus = pbus->parent;
> >> + }
> >> +
> >> + return false;
> >> +}
> >> +
> >> /* inject_lock must be held before calling */
> >> static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus)
> >> {
> >> @@ -118,6 +131,13 @@ static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus)
> >> if (bus_ops->bus == bus)
> >> return bus_ops->ops;
> >> }
> >> +
> >> + /* here can't find bus_ops, fall back to get bus_ops of upstream bus */
> >> + list_for_each_entry(bus_ops, &pci_bus_ops_list, list) {
> >> + if (pci_is_upstream_bus(bus, bus_ops->bus))
> >> + return bus_ops->ops;
> >> + }
> >> +
> >> return NULL;
> >> }
> >>
> >> @@ -506,6 +526,7 @@ static struct miscdevice aer_inject_device = {
> >> .fops = &aer_inject_fops,
> >> };
> >>
> >> +
> >> static int __init aer_inject_init(void)
> >> {
> >> return misc_register(&aer_inject_device);
> >
> > After
> >
> > # rmmod aer_inject
> >
> > What will happen?
> >
> > Best Regards,
> > Huang Ying
> >
> >
>
next prev parent reply other threads:[~2012-08-28 0:38 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-11 11:52 [PATCH 1/3] PCI/AER: Fix NULL pci_ops return when hotplug a pci bus which was doing aer error inject Yijing Wang
2012-08-11 11:52 ` [PATCH 2/3] PCI/AER: Clean pci_bus_ops when related pci bus was removed Yijing Wang
2012-08-25 9:59 ` [RESEND BUGFIX PATCH 2/3] PCI/AER: clean " Yijing Wang
2012-08-11 11:52 ` [PATCH 3/3] PCI: Check whether pci device has been removed when remove a pci device by sysfs Yijing Wang
2012-08-25 9:59 ` [RESEND BUGFIX PATCH 3/3] PCI: check " Yijing Wang
2012-08-25 14:39 ` Jiang Liu
2012-08-27 6:42 ` Yijing Wang
2012-08-25 9:59 ` [RESEND BUGFIX PATCH 1/3] PCI/AER: fix pci_ops return NULL when hotplug a pci bus which was doing aer error inject Yijing Wang
2012-08-27 1:23 ` Huang Ying
2012-08-27 15:05 ` Jiang Liu
2012-08-28 0:38 ` Huang Ying [this message]
2012-08-28 0:53 ` Yijing Wang
2012-08-27 8:49 ` Chen Gong
2012-08-28 0:47 ` Yijing Wang
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=1346114304.6279.341.camel@yhuang-dev \
--to=ying.huang@intel.com \
--cc=bhelgaas@google.com \
--cc=guohanjun@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=liuj97@gmail.com \
--cc=mchehab@redhat.com \
--cc=rusty@rustcorp.com.au \
--cc=wangyijing@huawei.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.