From 3e8db7e56082156a37b71d7334860c10fcea8025 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 1 Oct 2019 21:58:19 +0300 Subject: net: dsa: sja1105: Fix sleeping while atomic in .port_hwtstamp_set Currently this stack trace can be seen with CONFIG_DEBUG_ATOMIC_SLEEP=y: [ 41.568348] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909 [ 41.576757] in_atomic(): 1, irqs_disabled(): 0, pid: 208, name: ptp4l [ 41.583212] INFO: lockdep is turned off. [ 41.587123] CPU: 1 PID: 208 Comm: ptp4l Not tainted 5.3.0-rc6-01445-ge950f2d4bc7f-dirty #1827 [ 41.599873] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 41.607584] [] (show_stack) from [] (dump_stack+0xd4/0x100) [ 41.614863] [] (dump_stack) from [] (___might_sleep+0x1c8/0x2b4) [ 41.622574] [] (___might_sleep) from [] (__mutex_lock+0x48/0xab8) [ 41.630368] [] (__mutex_lock) from [] (mutex_lock_nested+0x1c/0x24) [ 41.638340] [] (mutex_lock_nested) from [] (sja1105_static_config_reload+0x30/0x27c) [ 41.647779] [] (sja1105_static_config_reload) from [] (sja1105_hwtstamp_set+0x108/0x1cc) [ 41.657562] [] (sja1105_hwtstamp_set) from [] (dev_ifsioc+0x18c/0x330) [ 41.665788] [] (dev_ifsioc) from [] (dev_ioctl+0x320/0x6e8) [ 41.673064] [] (dev_ioctl) from [] (sock_ioctl+0x334/0x5e8) [ 41.680340] [] (sock_ioctl) from [] (do_vfs_ioctl+0xb0/0xa10) [ 41.687789] [] (do_vfs_ioctl) from [] (ksys_ioctl+0x34/0x58) [ 41.695151] [] (ksys_ioctl) from [] (ret_fast_syscall+0x0/0x28) [ 41.702768] Exception stack(0xe8495fa8 to 0xe8495ff0) [ 41.707796] 5fa0: beff4a8c 00000001 00000011 000089b0 beff4a8c beff4a80 [ 41.715933] 5fc0: beff4a8c 00000001 0000000c 00000036 b6fa98c8 004e19c1 00000001 00000000 [ 41.724069] 5fe0: 004dcedc beff4a6c 004c0738 b6e7af4c [ 41.729860] BUG: scheduling while atomic: ptp4l/208/0x00000002 [ 41.735682] INFO: lockdep is turned off. Enabling RX timestamping will logically disturb the fastpath (processing of meta frames). Replace bool hwts_rx_en with a bit that is checked atomically from the fastpath and temporarily unset from the sleepable context during a change of the RX timestamping process (a destructive operation anyways, requires switch reset). If found unset, the fastpath (net/dsa/tag_sja1105.c) will just drop any received meta frame and not take the meta_lock at all. Fixes: a602afd200f5 ("net: dsa: sja1105: Expose PTP timestamping ioctls to userspace") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller --- include/linux/dsa/sja1105.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/dsa/sja1105.h b/include/linux/dsa/sja1105.h index 79435cfc20eb..897e799dbcb9 100644 --- a/include/linux/dsa/sja1105.h +++ b/include/linux/dsa/sja1105.h @@ -31,6 +31,8 @@ #define SJA1105_META_SMAC 0x222222222222ull #define SJA1105_META_DMAC 0x0180C200000Eull +#define SJA1105_HWTS_RX_EN 0 + /* Global tagger data: each struct sja1105_port has a reference to * the structure defined in struct sja1105_private. */ @@ -42,7 +44,7 @@ struct sja1105_tagger_data { * from taggers running on multiple ports on SMP systems */ spinlock_t meta_lock; - bool hwts_rx_en; + unsigned long state; }; struct sja1105_skb_cb { -- cgit v1.2.3