de5c95d0f5
bnxt_re_ib_reg acquires and releases the rtnl lock whenever it accesses the L2 driver. The following sequence can trigger a crash Acquires the rtnl_lock -> Registers roce driver callback with L2 driver -> release the rtnl lock bnxt_re acquires the rtnl_lock -> Request for MSIx vectors -> release the rtnl_lock Issue happens when bnxt_re proceeds with remaining part of initialization and L2 driver invokes bnxt_ulp_irq_stop as a part of bnxt_open_nic. The crash is in bnxt_qplib_nq_stop_irq as the NQ structures are not initialized yet, <snip> [ 3551.726647] BUG: unable to handle kernel NULL pointer dereference at (null) [ 3551.726656] IP: [<ffffffffc0840ee9>] bnxt_qplib_nq_stop_irq+0x59/0xb0 [bnxt_re] [ 3551.726674] PGD 0 [ 3551.726679] Oops: 0002 1 SMP ... [ 3551.726822] Hardware name: Dell Inc. PowerEdge R720/08RW36, BIOS 2.4.3 07/09/2014 [ 3551.726826] task: ffff97e30eec5ee0 ti: ffff97e3173bc000 task.ti: ffff97e3173bc000 [ 3551.726829] RIP: 0010:[<ffffffffc0840ee9>] [<ffffffffc0840ee9>] bnxt_qplib_nq_stop_irq+0x59/0xb0 [bnxt_re] ... [ 3551.726872] Call Trace: [ 3551.726886] [<ffffffffc082cb9e>] bnxt_re_stop_irq+0x4e/0x70 [bnxt_re] [ 3551.726899] [<ffffffffc07d6a53>] bnxt_ulp_irq_stop+0x43/0x70 [bnxt_en] [ 3551.726908] [<ffffffffc07c82f4>] bnxt_reserve_rings+0x174/0x1e0 [bnxt_en] [ 3551.726917] [<ffffffffc07cafd8>] __bnxt_open_nic+0x368/0x9a0 [bnxt_en] [ 3551.726925] [<ffffffffc07cb62b>] bnxt_open_nic+0x1b/0x50 [bnxt_en] [ 3551.726934] [<ffffffffc07cc62f>] bnxt_setup_mq_tc+0x11f/0x260 [bnxt_en] [ 3551.726943] [<ffffffffc07d5f58>] bnxt_dcbnl_ieee_setets+0xb8/0x1f0 [bnxt_en] [ 3551.726954] [<ffffffff890f983a>] dcbnl_ieee_set+0x9a/0x250 [ 3551.726966] [<ffffffff88fd6d21>] ? __alloc_skb+0xa1/0x2d0 [ 3551.726972] [<ffffffff890f72fa>] dcb_doit+0x13a/0x210 [ 3551.726981] [<ffffffff89003ff7>] rtnetlink_rcv_msg+0xa7/0x260 [ 3551.726989] [<ffffffff88ffdb00>] ? rtnl_unicast+0x20/0x30 [ 3551.726996] [<ffffffff88bf9dc8>] ? __kmalloc_node_track_caller+0x58/0x290 [ 3551.727002] [<ffffffff890f7326>] ? dcb_doit+0x166/0x210 [ 3551.727007] [<ffffffff88fd6d0d>] ? __alloc_skb+0x8d/0x2d0 [ 3551.727012] [<ffffffff89003f50>] ? rtnl_newlink+0x880/0x880 ... [ 3551.727104] [<ffffffff8911f7d5>] system_call_fastpath+0x1c/0x21 ... [ 3551.727164] RIP [<ffffffffc0840ee9>] bnxt_qplib_nq_stop_irq+0x59/0xb0 [bnxt_re] [ 3551.727175] RSP <ffff97e3173bf788> [ 3551.727177] CR2: 0000000000000000 Avoid this inconsistent state and system crash by acquiring the rtnl lock for the entire duration of device initialization. Re-factor the code to remove the rtnl lock from the individual function and acquire and release it from the caller. Fixes: |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.