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author | Bjorn Helgaas <bhelgaas@google.com> | 2017-09-15 09:33:51 +0300 |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2017-09-15 09:33:51 +0300 |
commit | 0f50a49e3008597abed0fff052d487f77db89093 (patch) | |
tree | b17952af59d6112187c5b5663fc546f9401adc3d /drivers/pci | |
parent | 711aab1dbb324d321e3d84368a435a78908c7bce (diff) | |
download | linux-0f50a49e3008597abed0fff052d487f77db89093.tar.xz |
Revert "PCI: Avoid race while enabling upstream bridges"
This reverts commit 40f11adc7cd9281227f0a6a627d966dd0a5f0cd9.
Jens found that iwlwifi firmware loading failed on a Lenovo X1 Carbon,
gen4:
iwlwifi 0000:04:00.0: Direct firmware load for iwlwifi-8000C-34.ucode failed with error -2
iwlwifi 0000:04:00.0: Direct firmware load for iwlwifi-8000C-33.ucode failed with error -2
iwlwifi 0000:04:00.0: Direct firmware load for iwlwifi-8000C-32.ucode failed with error -2
iwlwifi 0000:04:00.0: loaded firmware version 31.532993.0 op_mode iwlmvm
iwlwifi 0000:04:00.0: Detected Intel(R) Dual Band Wireless AC 8260, REV=0x208
...
iwlwifi 0000:04:00.0: Failed to load firmware chunk!
iwlwifi 0000:04:00.0: Could not load the [0] uCode section
iwlwifi 0000:04:00.0: Failed to start INIT ucode: -110
iwlwifi 0000:04:00.0: Failed to run INIT ucode: -110
He bisected it to 40f11adc7cd9 ("PCI: Avoid race while enabling upstream
bridges"). Revert that commit to fix the regression.
Link: http://lkml.kernel.org/r/4bcbcbc1-7c79-09f0-5071-bc2f53bf6574@kernel.dk
Fixes: 40f11adc7cd9 ("PCI: Avoid race while enabling upstream bridges")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Srinath Mannam <srinath.mannam@broadcom.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Luca Coelho <luca@coelho.fi>
CC: Johannes Berg <johannes@sipsolutions.net>
CC: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/pci.c | 13 |
1 files changed, 2 insertions, 11 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b0002daa50f3..6078dfc11b11 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -52,7 +52,6 @@ static void pci_pme_list_scan(struct work_struct *work); static LIST_HEAD(pci_pme_list); static DEFINE_MUTEX(pci_pme_list_mutex); static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan); -static DEFINE_MUTEX(pci_bridge_mutex); struct pci_pme_device { struct list_head list; @@ -1351,16 +1350,10 @@ static void pci_enable_bridge(struct pci_dev *dev) if (bridge) pci_enable_bridge(bridge); - /* - * Hold pci_bridge_mutex to prevent a race when enabling two - * devices below the bridge simultaneously. The race may cause a - * PCI_COMMAND_MEMORY update to be lost (see changelog). - */ - mutex_lock(&pci_bridge_mutex); if (pci_is_enabled(dev)) { if (!dev->is_busmaster) pci_set_master(dev); - goto end; + return; } retval = pci_enable_device(dev); @@ -1368,8 +1361,6 @@ static void pci_enable_bridge(struct pci_dev *dev) dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval); pci_set_master(dev); -end: - mutex_unlock(&pci_bridge_mutex); } static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) @@ -1394,7 +1385,7 @@ static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) return 0; /* already enabled */ bridge = pci_upstream_bridge(dev); - if (bridge && !pci_is_enabled(bridge)) + if (bridge) pci_enable_bridge(bridge); /* only skip sriov related */ |