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Dennis Dalessandro authored
We need to do some rework on the dummy netdev. Calling the free_netdev() would normally make sense, and that will be addressed in an upcoming patch. For now just revert the behavior to what it was before keeping the unused variable removal part of the patch. The dd->dumm_netdev is mainly used for packet receiving through alloc_netdev_mqs() for typical net devices. A a result, it should be freed with kfree instead of free_netdev() that leads to a crash when unloading the hfi1 module: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8000000855b54067 P4D 8000000855b54067 PUD 84a4f5067 PMD 0 Oops: 0000 [#1] SMP PTI CPU: 73 PID: 10299 Comm: modprobe Not tainted 5.6.0-rc5+ #1 Hardware name: Intel Corporation S2600WT2R/S2600WT2R, BIOS SE5C610.86B.01.01.0016.033120161139 03/31/2016 RIP: 0010:__hw_addr_flush+0x12/0x80 Code: 40 00 48 83 c4 08 4c 89 e7 5b 5d 41 5c e9 76 77 18 00 66 0f 1f 44 00 00 0f 1f 44 00 00 41 54 49 89 fc 55 53 48 8b 1f 48 39 df <48> 8b 2b 75 08 eb 4a 48 89 eb 48 89 c5 48 89 df e8 99 bf d0 ff 84 RSP: 0018:ffffb40e08783db8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002 RDX: ffffb40e00000000 RSI: 0000000000000246 RDI: ffff88ab13662298 RBP: ffff88ab13662000 R08: 0000000000001549 R09: 0000000000001549 R10: 0000000000000001 R11: 0000000000aaaaaa R12: ffff88ab13662298 R13: ffff88ab1b259e20 R14: ffff88ab1b259e42 R15: 0000000000000000 FS: 00007fb39b534740(0000) GS:ffff88b31f940000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000084d3ea004 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dev_addr_flush+0x15/0x30 free_netdev+0x7e/0x130 hfi1_netdev_free+0x59/0x70 [hfi1] remove_one+0x65/0x110 [hfi1] pci_device_remove+0x3b/0xc0 device_release_driver_internal+0xec/0x1b0 driver_detach+0x46/0x90 bus_remove_driver+0x58/0xd0 pci_unregister_driver+0x26/0xa0 hfi1_mod_cleanup+0xc/0xd54 [hfi1] __x64_sys_delete_module+0x16c/0x260 ? exit_to_usermode_loop+0xa4/0xc0 do_syscall_64+0x5b/0x200 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 193ba031 ("IB/hfi1: Use free_netdev() in hfi1_netdev_free()") Link: https://lore.kernel.org/r/20200623203224.106975.16926.stgit@awfm-01.aw.intel.comReviewed-by:
Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by:
Kaike Wan <kaike.wan@intel.com> Signed-off-by:
Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by:
Jason Gunthorpe <jgg@nvidia.com>
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