From: Bjorn Helgaas <helgaas@kernel.org>
To: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: linux-pci@vger.kernel.org, devel@linuxdriverproject.org,
linux-kernel@vger.kernel.org,
"K. Y. Srinivasan" <kys@microsoft.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Bjorn Helgaas <bhelgaas@google.com>,
Jake Oshins <jakeo@microsoft.com>
Subject: Re: [PATCH] PCI: hv: report resources release after stopping the bus
Date: Mon, 2 May 2016 15:43:03 -0500 [thread overview]
Message-ID: <20160502204303.GL24851@localhost> (raw)
In-Reply-To: <1461922750-26053-1-git-send-email-vkuznets@redhat.com>
On Fri, Apr 29, 2016 at 11:39:10AM +0200, Vitaly Kuznetsov wrote:
> Kernel hang is observed when pci-hyperv module is release with device
> drivers still attached. E.g. when I do 'rmmod pci_hyperv' with BCM5720
> device pass-through-ed (tg3 module) I see the following:
>
> NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [rmmod:2104]
> ...
> Call Trace:
> [<ffffffffa0641487>] tg3_read_mem+0x87/0x100 [tg3]
> [<ffffffffa063f000>] ? 0xffffffffa063f000
> [<ffffffffa0644375>] tg3_poll_fw+0x85/0x150 [tg3]
> [<ffffffffa0649877>] tg3_chip_reset+0x357/0x8c0 [tg3]
> [<ffffffffa064ca8b>] tg3_halt+0x3b/0x190 [tg3]
> [<ffffffffa0657611>] tg3_stop+0x171/0x230 [tg3]
> ...
> [<ffffffffa064c550>] tg3_remove_one+0x90/0x140 [tg3]
> [<ffffffff813bee59>] pci_device_remove+0x39/0xc0
> [<ffffffff814a3201>] __device_release_driver+0xa1/0x160
> [<ffffffff814a32e3>] device_release_driver+0x23/0x30
> [<ffffffff813b794a>] pci_stop_bus_device+0x8a/0xa0
> [<ffffffff813b7ab6>] pci_stop_root_bus+0x36/0x60
> [<ffffffffa02c3f38>] hv_pci_remove+0x238/0x260 [pci_hyperv]
>
> The problem seems to be that we report local resources release before
> stopping the bus and removing devices from it and device drivers may
> try to perform some operations with these resources on shutdown. Move
> resources release report after we do pci_stop_root_bus().
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Applied with Jake's ack to pci/host-hv for v4.7, thanks, Vitaly!
> ---
> drivers/pci/host/pci-hyperv.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c
> index f2559b6..c17e792 100644
> --- a/drivers/pci/host/pci-hyperv.c
> +++ b/drivers/pci/host/pci-hyperv.c
> @@ -2268,11 +2268,6 @@ static int hv_pci_remove(struct hv_device *hdev)
>
> hbus = hv_get_drvdata(hdev);
>
> - ret = hv_send_resources_released(hdev);
> - if (ret)
> - dev_err(&hdev->device,
> - "Couldn't send resources released packet(s)\n");
> -
> memset(&pkt.teardown_packet, 0, sizeof(pkt.teardown_packet));
> init_completion(&comp_pkt.host_event);
> pkt.teardown_packet.completion_func = hv_pci_generic_compl;
> @@ -2295,6 +2290,11 @@ static int hv_pci_remove(struct hv_device *hdev)
> pci_unlock_rescan_remove();
> }
>
> + ret = hv_send_resources_released(hdev);
> + if (ret)
> + dev_err(&hdev->device,
> + "Couldn't send resources released packet(s)\n");
> +
> vmbus_close(hdev->channel);
>
> /* Delete any children which might still exist. */
> --
> 2.5.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
prev parent reply other threads:[~2016-05-02 20:43 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-29 9:39 [PATCH] PCI: hv: report resources release after stopping the bus Vitaly Kuznetsov
2016-04-29 16:55 ` Jake Oshins
2016-05-02 20:43 ` Bjorn Helgaas [this message]
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=20160502204303.GL24851@localhost \
--to=helgaas@kernel.org \
--cc=bhelgaas@google.com \
--cc=devel@linuxdriverproject.org \
--cc=haiyangz@microsoft.com \
--cc=jakeo@microsoft.com \
--cc=kys@microsoft.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=vkuznets@redhat.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).