On Tue, Jun 25, 2019 at 7:40 PM Vladimir Oltean <olte...@gmail.com> wrote:
>
> Currently when the driver unloads and PTP is enabled, the delayed work
> that prevents the timecounter from expiring becomes a ticking time bomb.
> The kernel will schedule the work thread within 60 seconds of driver
> removal, but the work handler is no longer there, leading to this
> strange and inconclusive stack trace:
>
> [ 64.473112] Unable to handle kernel paging request at virtual address
> 79746970
> [ 64.480340] pgd = 008c4af9
> [ 64.483042] [79746970] *pgd=00000000
> [ 64.486620] Internal error: Oops: 80000005 [#1] SMP ARM
> [ 64.491820] Modules linked in:
> [ 64.494871] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
> 5.2.0-rc5-01634-ge3a2773ba9e5 #1246
> [ 64.503007] Hardware name: Freescale LS1021A
> [ 64.507259] PC is at 0x79746970
> [ 64.510393] LR is at call_timer_fn+0x3c/0x18c
> [ 64.514729] pc : [<79746970>] lr : [<c03bd734>] psr: 60010113
> [ 64.520965] sp : c1901de0 ip : 00000000 fp : c1903080
> [ 64.526163] r10: c1901e38 r9 : ffffe000 r8 : c19064ac
> [ 64.531363] r7 : 79746972 r6 : e98dd260 r5 : 00000100 r4 : c1a9e4a0
> [ 64.537859] r3 : c1900000 r2 : ffffa400 r1 : 79746972 r0 : e98dd260
> [ 64.544359] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment
> none
> [ 64.551460] Control: 10c5387d Table: a8a2806a DAC: 00000051
> [ 64.557176] Process swapper/0 (pid: 0, stack limit = 0x1ddb27f0)
> [ 64.563147] Stack: (0xc1901de0 to 0xc1902000)
> [ 64.567481] 1de0: eb6a4918 3d60d7c3 c1a9e554 e98dd260 eb6a34c0 c1a9e4a0
> ffffa400 c19064ac
> [ 64.575616] 1e00: ffffe000 c03bd95c c1901e34 c1901e34 eb6a34c0 c1901e30
> c1903d00 c186f4c0
> [ 64.583751] 1e20: c1906488 29e34000 c1903080 c03bdca4 00000000 eaa6f218
> 00000000 eb6a45c0
> [ 64.591886] 1e40: eb6a45c0 20010193 00000003 c03c0a68 20010193 3f7231be
> c1903084 00000002
> [ 64.600022] 1e60: 00000082 00000001 ffffe000 c1a9e0a4 00000100 c0302298
> 02b64722 0000000f
> [ 64.608157] 1e80: c186b3c8 c1877540 c19064ac 0000000a c186b350 ffffa401
> c1903d00 c1107348
> [ 64.616292] 1ea0: 00200102 c0d87a14 ea823c00 ffffe000 00000012 00000000
> 00000000 ea810800
> [ 64.624427] 1ec0: f0803000 c1876ba8 00000000 c034c784 c18774b8 c039fb50
> c1906c90 c1978aac
> [ 64.632562] 1ee0: f080200c f0802000 c1901f10 c0709ca8 c03091a0 60010013
> ffffffff c1901f44
> [ 64.640697] 1f00: 00000000 c1900000 c1876ba8 c0301a8c 00000000 000070a0
> eb6ac1a0 c031da60
> [ 64.648832] 1f20: ffffe000 c19064ac c19064f0 00000001 00000000 c1906488
> c1876ba8 00000000
> [ 64.656967] 1f40: ffffffff c1901f60 c030919c c03091a0 60010013 ffffffff
> 00000051 00000000
> [ 64.665102] 1f60: ffffe000 c0376aa4 c1a9da37 ffffffff 00000037 3f7231be
> c1ab20c0 000000cc
> [ 64.673238] 1f80: c1906488 c1906480 ffffffff 00000037 c1ab20c0 c1ab20c0
> 00000001 c0376e1c
> [ 64.681373] 1fa0: c1ab2118 c1700ea8 ffffffff ffffffff 00000000 c1700754
> c17dfa40 ebfffd80
> [ 64.689509] 1fc0: 00000000 c17dfa40 3f7733be 00000000 00000000 c1700330
> 00000051 10c0387d
> [ 64.697644] 1fe0: 00000000 8f000000 410fc075 10c5387d 00000000 00000000
> 00000000 00000000
> [ 64.705788] [<c03bd734>] (call_timer_fn) from [<c03bd95c>]
> (expire_timers+0xd8/0x144)
> [ 64.713579] [<c03bd95c>] (expire_timers) from [<c03bdca4>]
> (run_timer_softirq+0xe4/0x1dc)
> [ 64.721716] [<c03bdca4>] (run_timer_softirq) from [<c0302298>]
> (__do_softirq+0x130/0x3c8)
> [ 64.729854] [<c0302298>] (__do_softirq) from [<c034c784>]
> (irq_exit+0xbc/0xd8)
> [ 64.737040] [<c034c784>] (irq_exit) from [<c039fb50>]
> (__handle_domain_irq+0x60/0xb4)
> [ 64.744833] [<c039fb50>] (__handle_domain_irq) from [<c0709ca8>]
> (gic_handle_irq+0x58/0x9c)
> [ 64.753143] [<c0709ca8>] (gic_handle_irq) from [<c0301a8c>]
> (__irq_svc+0x6c/0x90)
> [ 64.760583] Exception stack(0xc1901f10 to 0xc1901f58)
> [ 64.765605] 1f00: 00000000 000070a0
> eb6ac1a0 c031da60
> [ 64.773740] 1f20: ffffe000 c19064ac c19064f0 00000001 00000000 c1906488
> c1876ba8 00000000
> [ 64.781873] 1f40: ffffffff c1901f60 c030919c c03091a0 60010013 ffffffff
> [ 64.788456] [<c0301a8c>] (__irq_svc) from [<c03091a0>]
> (arch_cpu_idle+0x38/0x3c)
> [ 64.795816] [<c03091a0>] (arch_cpu_idle) from [<c0376aa4>]
> (do_idle+0x1bc/0x298)
> [ 64.803175] [<c0376aa4>] (do_idle) from [<c0376e1c>]
> (cpu_startup_entry+0x18/0x1c)
> [ 64.810707] [<c0376e1c>] (cpu_startup_entry) from [<c1700ea8>]
> (start_kernel+0x480/0x4ac)
> [ 64.818839] Code: bad PC value
> [ 64.821890] ---[ end trace e226ed97b1c584cd ]---
> [ 64.826482] Kernel panic - not syncing: Fatal exception in interrupt
> [ 64.832807] CPU1: stopping
> [ 64.835501] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G D
> 5.2.0-rc5-01634-ge3a2773ba9e5 #1246
> [ 64.845013] Hardware name: Freescale LS1021A
> [ 64.849266] [<c0312394>] (unwind_backtrace) from [<c030cc74>]
> (show_stack+0x10/0x14)
> [ 64.856972] [<c030cc74>] (show_stack) from [<c0ff4138>]
> (dump_stack+0xb4/0xc8)
> [ 64.864159] [<c0ff4138>] (dump_stack) from [<c0310854>]
> (handle_IPI+0x3bc/0x3dc)
> [ 64.871519] [<c0310854>] (handle_IPI) from [<c0709ce8>]
> (gic_handle_irq+0x98/0x9c)
> [ 64.879050] [<c0709ce8>] (gic_handle_irq) from [<c0301a8c>]
> (__irq_svc+0x6c/0x90)
> [ 64.886489] Exception stack(0xea8cbf60 to 0xea8cbfa8)
> [ 64.891514] bf60: 00000000 0000307c eb6c11a0 c031da60 ffffe000 c19064ac
> c19064f0 00000002
> [ 64.899649] bf80: 00000000 c1906488 c1876ba8 00000000 00000000 ea8cbfb0
> c030919c c03091a0
> [ 64.907780] bfa0: 600d0013 ffffffff
> [ 64.911250] [<c0301a8c>] (__irq_svc) from [<c03091a0>]
> (arch_cpu_idle+0x38/0x3c)
> [ 64.918609] [<c03091a0>] (arch_cpu_idle) from [<c0376aa4>]
> (do_idle+0x1bc/0x298)
> [ 64.925967] [<c0376aa4>] (do_idle) from [<c0376e1c>]
> (cpu_startup_entry+0x18/0x1c)
> [ 64.933496] [<c0376e1c>] (cpu_startup_entry) from [<803025cc>] (0x803025cc)
> [ 64.940422] Rebooting in 3 seconds..
>
> In this case, what happened is that the DSA driver failed to probe at
> boot time due to a PHY issue during phylink_connect_phy:
>
> [ 2.245607] fsl-gianfar soc:ethernet@2d90000 eth2: error -19 setting up
> slave phy
> [ 2.258051] sja1105 spi0.1: failed to create slave for port 0.0
>
> Fixes: bb77f36ac21d ("net: dsa: sja1105: Add support for the PTP clock")
> Signed-off-by: Vladimir Oltean <olte...@gmail.com>
Acked-by: Willem de Bruijn <will...@google.com>
