linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jiantao Zhang <water.zhangjiantao@huawei.com>
To: <bhelgaas@google.com>, <linux-pci@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <zhangjianrong5@huawei.com>
Cc: <suzhuangluan@hisilicon.com>, <caiyadong@huawei.com>,
	<guhengsheng@hisilicon.com>, <songxiaowei@hisilicon.com>,
	<water.zhangjiantao@huawei.com>
Subject: [PATCH] PCI: Exit restore process when device is still powerdown
Date: Thu, 22 Dec 2022 12:41:04 +0000	[thread overview]
Message-ID: <20221222124104.69607-1-water.zhangjiantao@huawei.com> (raw)

We get this stack when the rp doesn't power up in resume noirq:
    dump_backtrace.cfi_jt+0x0/0x4
    dump_stack_lvl+0xb4/0x10c
    show_regs_before_dump_stack+0x1c/0x30
    arm64_serror_panic+0x110/0x1a8
    do_serror+0x16c/0x1cc
    el1_error+0x8c/0x10c
    do_raw_spin_unlock+0x74/0xdc
    pci_bus_read_config_word+0xdc/0x1dc
    pci_restore_msi_state+0x2f4/0x36c
    pci_restore_state+0x13f0/0x1444
    pci_pm_resume_noirq+0x158/0x318
    dpm_run_callback+0x178/0x5e8
    device_resume_noirq+0x250/0x264
    async_resume_noirq+0x20/0xf8
    async_run_entry_fn+0xfc/0x364
    process_one_work+0x37c/0x7f4
    worker_thread+0x3e8/0x754
    kthread+0x168/0x204
    ret_from_fork+0x10/0x18
The ep device uses msix, the restore process will write bar space
in __pci_msix_desc_mask_irq, which will result in accessing the
powerdown area when the rp doesn't power on.

It makes sense we should do nothing when the device is still powerdown.

Signed-off-by: Jianrong Zhang <zhangjianrong5@huawei.com>
Signed-off-by: Jiantao Zhang <water.zhangjiantao@huawei.com>
---
 drivers/pci/pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index fba95486caaf..279f6e8c5a00 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1764,7 +1764,7 @@ static void pci_restore_rebar_state(struct pci_dev *pdev)
  */
 void pci_restore_state(struct pci_dev *dev)
 {
-	if (!dev->state_saved)
+	if (!dev->state_saved || dev->current_state == PCI_UNKNOWN)
 		return;
 
 	/*
-- 
2.17.1


             reply	other threads:[~2022-12-22 12:41 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-22 12:41 Jiantao Zhang [this message]
2023-01-12 22:13 ` [PATCH] PCI: Exit restore process when device is still powerdown Bjorn Helgaas
     [not found] <4691af50-b718-d0ec-7dff-fd6fa1ff081a@huawei.com>
2023-01-20  6:18 ` jiantao zhang
2023-01-20 16:53   ` Bjorn Helgaas

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=20221222124104.69607-1-water.zhangjiantao@huawei.com \
    --to=water.zhangjiantao@huawei.com \
    --cc=bhelgaas@google.com \
    --cc=caiyadong@huawei.com \
    --cc=guhengsheng@hisilicon.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=songxiaowei@hisilicon.com \
    --cc=suzhuangluan@hisilicon.com \
    --cc=zhangjianrong5@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 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).