diff options
| author | Vaibhav Jain <vaibhav@linux.vnet.ibm.com> | 2017-06-02 22:26:48 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-06-06 19:09:27 +1000 |
| commit | b3aa20ba2ba8072b73bd799605b8c98927b7056c (patch) | |
| tree | 6ddde853e65ffba8135727a1288f157f23e6c9e5 /drivers/misc | |
| parent | 7f22ced4377628074e2ac25f41a88f98eb3b03f1 (diff) | |
| download | linux-rt-b3aa20ba2ba8072b73bd799605b8c98927b7056c.tar.gz | |
cxl: Avoid double free_irq() for psl,slice interrupts
During an eeh call to cxl_remove can result in double free_irq of
psl,slice interrupts. This can happen if perst_reloads_same_image == 1
and call to cxl_configure_adapter() fails during slot_reset
callback. In such a case we see a kernel oops with following back-trace:
Oops: Kernel access of bad area, sig: 11 [#1]
Call Trace:
free_irq+0x88/0xd0 (unreliable)
cxl_unmap_irq+0x20/0x40 [cxl]
cxl_native_release_psl_irq+0x78/0xd8 [cxl]
pci_deconfigure_afu+0xac/0x110 [cxl]
cxl_remove+0x104/0x210 [cxl]
pci_device_remove+0x6c/0x110
device_release_driver_internal+0x204/0x2e0
pci_stop_bus_device+0xa0/0xd0
pci_stop_and_remove_bus_device+0x28/0x40
pci_hp_remove_devices+0xb0/0x150
pci_hp_remove_devices+0x68/0x150
eeh_handle_normal_event+0x140/0x580
eeh_handle_event+0x174/0x360
eeh_event_handler+0x1e8/0x1f0
This patch fixes the issue of double free_irq by checking that
variables that hold the virqs (err_hwirq, serr_hwirq, psl_virq) are
not '0' before un-mapping and resetting these variables to '0' when
they are un-mapped.
Cc: stable@vger.kernel.org
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/cxl/native.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c index 871a2f09c718..8d6ea9712dbd 100644 --- a/drivers/misc/cxl/native.c +++ b/drivers/misc/cxl/native.c @@ -1302,13 +1302,16 @@ int cxl_native_register_psl_err_irq(struct cxl *adapter) void cxl_native_release_psl_err_irq(struct cxl *adapter) { - if (adapter->native->err_virq != irq_find_mapping(NULL, adapter->native->err_hwirq)) + if (adapter->native->err_virq == 0 || + adapter->native->err_virq != + irq_find_mapping(NULL, adapter->native->err_hwirq)) return; cxl_p1_write(adapter, CXL_PSL_ErrIVTE, 0x0000000000000000); cxl_unmap_irq(adapter->native->err_virq, adapter); cxl_ops->release_one_irq(adapter, adapter->native->err_hwirq); kfree(adapter->irq_name); + adapter->native->err_virq = 0; } int cxl_native_register_serr_irq(struct cxl_afu *afu) @@ -1346,13 +1349,15 @@ int cxl_native_register_serr_irq(struct cxl_afu *afu) void cxl_native_release_serr_irq(struct cxl_afu *afu) { - if (afu->serr_virq != irq_find_mapping(NULL, afu->serr_hwirq)) + if (afu->serr_virq == 0 || + afu->serr_virq != irq_find_mapping(NULL, afu->serr_hwirq)) return; cxl_p1n_write(afu, CXL_PSL_SERR_An, 0x0000000000000000); cxl_unmap_irq(afu->serr_virq, afu); cxl_ops->release_one_irq(afu->adapter, afu->serr_hwirq); kfree(afu->err_irq_name); + afu->serr_virq = 0; } int cxl_native_register_psl_irq(struct cxl_afu *afu) @@ -1375,12 +1380,15 @@ int cxl_native_register_psl_irq(struct cxl_afu *afu) void cxl_native_release_psl_irq(struct cxl_afu *afu) { - if (afu->native->psl_virq != irq_find_mapping(NULL, afu->native->psl_hwirq)) + if (afu->native->psl_virq == 0 || + afu->native->psl_virq != + irq_find_mapping(NULL, afu->native->psl_hwirq)) return; cxl_unmap_irq(afu->native->psl_virq, afu); cxl_ops->release_one_irq(afu->adapter, afu->native->psl_hwirq); kfree(afu->psl_irq_name); + afu->native->psl_virq = 0; } static void recover_psl_err(struct cxl_afu *afu, u64 errstat) |