003bcee66a
commit 936bd03405fc83ba039d42bc93ffd4b88418f1d3 upstream. Running tests with a debug kernel shows that bnx2fc_recv_frame() is modifying the per_cpu lport stats counters in a non-mpsafe way. Just boot a debug kernel and run the bnx2fc driver with the hardware enabled. [ 1391.699147] BUG: using smp_processor_id() in preemptible [00000000] code: bnx2fc_ [ 1391.699160] caller is bnx2fc_recv_frame+0xbf9/0x1760 [bnx2fc] [ 1391.699174] CPU: 2 PID: 4355 Comm: bnx2fc_l2_threa Kdump: loaded Tainted: G B [ 1391.699180] Hardware name: HP ProLiant DL120 G7, BIOS J01 07/01/2013 [ 1391.699183] Call Trace: [ 1391.699188] dump_stack_lvl+0x57/0x7d [ 1391.699198] check_preemption_disabled+0xc8/0xd0 [ 1391.699205] bnx2fc_recv_frame+0xbf9/0x1760 [bnx2fc] [ 1391.699215] ? do_raw_spin_trylock+0xb5/0x180 [ 1391.699221] ? bnx2fc_npiv_create_vports.isra.0+0x4e0/0x4e0 [bnx2fc] [ 1391.699229] ? bnx2fc_l2_rcv_thread+0xb7/0x3a0 [bnx2fc] [ 1391.699240] bnx2fc_l2_rcv_thread+0x1af/0x3a0 [bnx2fc] [ 1391.699250] ? bnx2fc_ulp_init+0xc0/0xc0 [bnx2fc] [ 1391.699258] kthread+0x364/0x420 [ 1391.699263] ? _raw_spin_unlock_irq+0x24/0x50 [ 1391.699268] ? set_kthread_struct+0x100/0x100 [ 1391.699273] ret_from_fork+0x22/0x30 Restore the old get_cpu/put_cpu code with some modifications to reduce the size of the critical section. Link: https://lore.kernel.org/r/20220124145110.442335-1-jmeneghi@redhat.com Fixes: d576a5e80cd0 ("bnx2fc: Improve stats update mechanism") Tested-by: Guangwu Zhang <guazhang@redhat.com> Acked-by: Saurav Kashyap <skashyap@marvell.com> Signed-off-by: John Meneghini <jmeneghi@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.