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author | Vaibhav Jain <vaibhav@linux.vnet.ibm.com> | 2017-04-27 08:23:25 +0300 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-05-02 15:41:41 +0300 |
commit | ea9a26d117cf0637c71d3e0076f4a124bf5859df (patch) | |
tree | fbf66bb66073e35cac76916f9df693a127834632 | |
parent | 084a275e4c9477c432b05e872c3a297eab41638a (diff) | |
download | linux-ea9a26d117cf0637c71d3e0076f4a124bf5859df.tar.xz |
cxl: Force context lock during EEH flow
During an eeh event when the cxl card is fenced and card sysfs attr
perst_reloads_same_image is set following warning message is seen in the
kernel logs:
Adapter context unlocked with 0 active contexts
------------[ cut here ]------------
WARNING: CPU: 12 PID: 627 at
../drivers/misc/cxl/main.c:325 cxl_adapter_context_unlock+0x60/0x80 [cxl]
Even though this warning is harmless, it clutters the kernel log
during an eeh event. This warning is triggered as the EEH callback
cxl_pci_error_detected doesn't obtain a context-lock before forcibly
detaching all active context and when context-lock is released during
call to cxl_configure_adapter from cxl_pci_slot_reset, a warning in
cxl_adapter_context_unlock is triggered.
To fix this warning, we acquire the adapter context-lock via
cxl_adapter_context_lock() in the eeh callback
cxl_pci_error_detected() once all the virtual AFU PHBs are notified
and their contexts detached. The context-lock is released in
cxl_pci_slot_reset() after the adapter is successfully reconfigured
and before the we call the slot_reset callback on slice attached
device-drivers.
Fixes: 70b565bbdb91 ("cxl: Prevent adapter reset if an active context exists")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Tested-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
-rw-r--r-- | drivers/misc/cxl/pci.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index fe01a0e00f37..556ef910a651 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -1716,8 +1716,6 @@ static int cxl_configure_adapter(struct cxl *adapter, struct pci_dev *dev) if ((rc = cxl_native_register_psl_err_irq(adapter))) goto err; - /* Release the context lock as adapter is configured */ - cxl_adapter_context_unlock(adapter); return 0; err: @@ -1861,6 +1859,9 @@ static struct cxl *cxl_pci_init_adapter(struct pci_dev *dev) if ((rc = cxl_sysfs_adapter_add(adapter))) goto err_put1; + /* Release the context lock as adapter is configured */ + cxl_adapter_context_unlock(adapter); + return adapter; err_put1: @@ -2171,6 +2172,13 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev, cxl_ops->afu_deactivate_mode(afu, afu->current_mode); pci_deconfigure_afu(afu); } + + /* should take the context lock here */ + if (cxl_adapter_context_lock(adapter) != 0) + dev_warn(&adapter->dev, + "Couldn't take context lock with %d active-contexts\n", + atomic_read(&adapter->contexts_num)); + cxl_deconfigure_adapter(adapter); return result; @@ -2189,6 +2197,13 @@ static pci_ers_result_t cxl_pci_slot_reset(struct pci_dev *pdev) if (cxl_configure_adapter(adapter, pdev)) goto err; + /* + * Unlock context activation for the adapter. Ideally this should be + * done in cxl_pci_resume but cxlflash module tries to activate the + * master context as part of slot_reset callback. + */ + cxl_adapter_context_unlock(adapter); + for (i = 0; i < adapter->slices; i++) { afu = adapter->afu[i]; |