From fc7a99fb71b83f811e2c013ab55e507048153f23 Mon Sep 17 00:00:00 2001 From: Mugunthan V N Date: Mon, 13 Oct 2014 22:21:06 +0530 Subject: [PATCH] drivers: net: davinci_cpdma: remove spinlock as SOFTIRQ-unsafe lock order detected remove spinlock in cpdma_desc_pool_destroy() as there is no active cpdma channel and iounmap should be called without auquiring lock. root@dra7xx-evm:~# modprobe -r ti_cpsw [ 50.539743] [ 50.541312] ====================================================== [ 50.547796] [ INFO: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected ] [ 50.554826] 3.14.19-02124-g95c5b7b #308 Not tainted [ 50.559939] ------------------------------------------------------ [ 50.566416] modprobe/1921 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: [ 50.573347] (vmap_area_lock){+.+...}, at: [] find_vmap_area+0x10/0x6c [ 50.581132] [ 50.581132] and this task is already holding: [ 50.587249] (&(&pool->lock)->rlock#2){..-...}, at: [] cpdma_ctlr_destroy+0x5c/0x114 [davinci_cpdma] [ 50.597766] which would create a new lock dependency: [ 50.603048] (&(&pool->lock)->rlock#2){..-...} -> (vmap_area_lock){+.+...} [ 50.610296] [ 50.610296] but this new dependency connects a SOFTIRQ-irq-safe lock: [ 50.618601] (&(&pool->lock)->rlock#2){..-...} ... which became SOFTIRQ-irq-safe at: [ 50.626829] [] _raw_spin_lock_irqsave+0x38/0x4c [ 50.632677] [] cpdma_desc_free.constprop.7+0x28/0x58 [davinci_cpdma] [ 50.640437] [] __cpdma_chan_free+0x7c/0xa8 [davinci_cpdma] [ 50.647289] [] __cpdma_chan_process+0xf4/0x134 [davinci_cpdma] [ 50.654512] [] cpdma_chan_process+0x3c/0x54 [davinci_cpdma] [ 50.661455] [] cpsw_poll+0x14/0xa8 [ti_cpsw] [ 50.667038] [] net_rx_action+0xc0/0x1e8 [ 50.672150] [] __do_softirq+0xcc/0x304 [ 50.677183] [] irq_exit+0xa8/0xfc [ 50.681751] [] handle_IRQ+0x50/0xb0 [ 50.686513] [] gic_handle_irq+0x28/0x5c [ 50.691628] [] __irq_svc+0x44/0x5c [ 50.696289] [] _raw_spin_unlock_irqrestore+0x34/0x44 [ 50.702591] [] do_page_fault.part.9+0x144/0x3c4 [ 50.708433] [] do_page_fault+0x74/0x84 [ 50.713453] [] do_DataAbort+0x34/0x98 [ 50.718391] [] __dabt_usr+0x3c/0x40 [ 50.723148] [ 50.723148] to a SOFTIRQ-irq-unsafe lock: [ 50.728893] (vmap_area_lock){+.+...} ... which became SOFTIRQ-irq-unsafe at: [ 50.736476] ... [] _raw_spin_lock+0x28/0x38 [ 50.741876] [] alloc_vmap_area.isra.28+0xb8/0x300 [ 50.747908] [] __get_vm_area_node.isra.29+0x90/0x134 [ 50.754210] [] get_vm_area_caller+0x3c/0x48 [ 50.759692] [] vmap+0x40/0x78 [ 50.763900] [] check_writebuffer_bugs+0x54/0x1a0 [ 50.769835] [] start_kernel+0x320/0x388 [ 50.774952] [<80008074>] 0x80008074 [ 50.778793] [ 50.778793] other info that might help us debug this: [ 50.778793] [ 50.787181] Possible interrupt unsafe locking scenario: [ 50.787181] [ 50.794295] CPU0 CPU1 [ 50.799042] ---- ---- [ 50.803785] lock(vmap_area_lock); [ 50.807446] local_irq_disable(); [ 50.813652] lock(&(&pool->lock)->rlock#2); [ 50.820782] lock(vmap_area_lock); [ 50.827086] [ 50.829823] lock(&(&pool->lock)->rlock#2); [ 50.834490] [ 50.834490] *** DEADLOCK *** [ 50.834490] [ 50.840695] 4 locks held by modprobe/1921: [ 50.844981] #0: (&__lockdep_no_validate__){......}, at: [] driver_detach+0x44/0xb8 [ 50.854038] #1: (&__lockdep_no_validate__){......}, at: [] driver_detach+0x50/0xb8 [ 50.863102] #2: (&(&ctlr->lock)->rlock){......}, at: [] cpdma_ctlr_destroy+0x1c/0x114 [davinci_cpdma] [ 50.873890] #3: (&(&pool->lock)->rlock#2){..-...}, at: [] cpdma_ctlr_destroy+0x5c/0x114 [davinci_cpdma] [ 50.884871] the dependencies between SOFTIRQ-irq-safe lock and the holding lock: [ 50.892827] -> (&(&pool->lock)->rlock#2){..-...} ops: 167 { [ 50.898703] IN-SOFTIRQ-W at: [ 50.901995] [] _raw_spin_lock_irqsave+0x38/0x4c [ 50.909476] [] cpdma_desc_free.constprop.7+0x28/0x58 [davinci_cpdma] [ 50.918878] [] __cpdma_chan_free+0x7c/0xa8 [davinci_cpdma] [ 50.927366] [] __cpdma_chan_process+0xf4/0x134 [davinci_cpdma] [ 50.936218] [] cpdma_chan_process+0x3c/0x54 [davinci_cpdma] [ 50.944794] [] cpsw_poll+0x14/0xa8 [ti_cpsw] [ 50.952009] [] net_rx_action+0xc0/0x1e8 [ 50.958765] [] __do_softirq+0xcc/0x304 [ 50.965432] [] irq_exit+0xa8/0xfc [ 50.971635] [] handle_IRQ+0x50/0xb0 [ 50.978035] [] gic_handle_irq+0x28/0x5c [ 50.984788] [] __irq_svc+0x44/0x5c [ 50.991085] [] _raw_spin_unlock_irqrestore+0x34/0x44 [ 50.999023] [] do_page_fault.part.9+0x144/0x3c4 [ 51.006510] [] do_page_fault+0x74/0x84 [ 51.013171] [] do_DataAbort+0x34/0x98 [ 51.019738] [] __dabt_usr+0x3c/0x40 [ 51.026129] INITIAL USE at: [ 51.029335] [] _raw_spin_lock_irqsave+0x38/0x4c [ 51.036729] [] cpdma_chan_submit+0x4c/0x2f0 [davinci_cpdma] [ 51.045225] [] cpsw_ndo_open+0x378/0x6bc [ti_cpsw] [ 51.052897] [] __dev_open+0x9c/0x104 [ 51.059287] [] __dev_change_flags+0x88/0x160 [ 51.066420] [] dev_change_flags+0x18/0x48 [ 51.073270] [] devinet_ioctl+0x61c/0x6e0 [ 51.080029] [] sock_ioctl+0x5c/0x298 [ 51.086418] [] do_vfs_ioctl+0x78/0x61c [ 51.092993] [] SyS_ioctl+0x64/0x74 [ 51.099200] [] ret_fast_syscall+0x0/0x48 [ 51.105956] } [ 51.107696] ... key at: [] __key.21312+0x0/0xfffff650 [davinci_cpdma] [ 51.115912] ... acquired at: [ 51.119019] [] lock_acquire+0x9c/0x104 [ 51.124138] [] _raw_spin_lock+0x28/0x38 [ 51.129341] [] find_vmap_area+0x10/0x6c [ 51.134547] [] remove_vm_area+0x8/0x6c [ 51.139659] [] __vunmap+0x20/0xf8 [ 51.144318] [] __arm_iounmap+0x10/0x18 [ 51.149440] [] cpdma_ctlr_destroy+0xf0/0x114 [davinci_cpdma] [ 51.156560] [] cpsw_remove+0x48/0x8c [ti_cpsw] [ 51.162407] [] platform_drv_remove+0x18/0x1c [ 51.168063] [] __device_release_driver+0x70/0xc8 [ 51.174094] [] driver_detach+0xb4/0xb8 [ 51.179212] [] bus_remove_driver+0x4c/0x90 [ 51.184693] [] SyS_delete_module+0x10c/0x198 [ 51.190355] [] ret_fast_syscall+0x0/0x48 [ 51.195661] [ 51.197217] the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: [ 51.205986] -> (vmap_area_lock){+.+...} ops: 520 { [ 51.211032] HARDIRQ-ON-W at: [ 51.214321] [] _raw_spin_lock+0x28/0x38 [ 51.221090] [] alloc_vmap_area.isra.28+0xb8/0x300 [ 51.228750] [] __get_vm_area_node.isra.29+0x90/0x134 [ 51.236690] [] get_vm_area_caller+0x3c/0x48 [ 51.243811] [] vmap+0x40/0x78 [ 51.249654] [] check_writebuffer_bugs+0x54/0x1a0 [ 51.257239] [] start_kernel+0x320/0x388 [ 51.263994] [<80008074>] 0x80008074 [ 51.269474] SOFTIRQ-ON-W at: [ 51.272769] [] _raw_spin_lock+0x28/0x38 [ 51.279525] [] alloc_vmap_area.isra.28+0xb8/0x300 [ 51.287190] [] __get_vm_area_node.isra.29+0x90/0x134 [ 51.295126] [] get_vm_area_caller+0x3c/0x48 [ 51.302245] [] vmap+0x40/0x78 [ 51.308094] [] check_writebuffer_bugs+0x54/0x1a0 [ 51.315669] [] start_kernel+0x320/0x388 [ 51.322423] [<80008074>] 0x80008074 [ 51.327906] INITIAL USE at: [ 51.331112] [] _raw_spin_lock+0x28/0x38 [ 51.337775] [] alloc_vmap_area.isra.28+0xb8/0x300 [ 51.345352] [] __get_vm_area_node.isra.29+0x90/0x134 [ 51.353197] [] get_vm_area_caller+0x3c/0x48 [ 51.360224] [] vmap+0x40/0x78 [ 51.365977] [] check_writebuffer_bugs+0x54/0x1a0 [ 51.373464] [] start_kernel+0x320/0x388 [ 51.380131] [<80008074>] 0x80008074 [ 51.385517] } [ 51.387260] ... key at: [] vmap_area_lock+0x10/0x20 [ 51.393841] ... acquired at: [ 51.396945] [] lock_acquire+0x9c/0x104 [ 51.402060] [] _raw_spin_lock+0x28/0x38 [ 51.407266] [] find_vmap_area+0x10/0x6c [ 51.412478] [] remove_vm_area+0x8/0x6c [ 51.417592] [] __vunmap+0x20/0xf8 [ 51.422252] [] __arm_iounmap+0x10/0x18 [ 51.427369] [] cpdma_ctlr_destroy+0xf0/0x114 [davinci_cpdma] [ 51.434487] [] cpsw_remove+0x48/0x8c [ti_cpsw] [ 51.440336] [] platform_drv_remove+0x18/0x1c [ 51.446000] [] __device_release_driver+0x70/0xc8 [ 51.452031] [] driver_detach+0xb4/0xb8 [ 51.457147] [] bus_remove_driver+0x4c/0x90 [ 51.462628] [] SyS_delete_module+0x10c/0x198 [ 51.468289] [] ret_fast_syscall+0x0/0x48 [ 51.473584] [ 51.475140] [ 51.475140] stack backtrace: [ 51.479703] CPU: 0 PID: 1921 Comm: modprobe Not tainted 3.14.19-02124-g95c5b7b #308 [ 51.487744] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 51.495865] [] (show_stack) from [] (dump_stack+0x78/0x94) [ 51.503444] [] (dump_stack) from [] (check_usage+0x408/0x594) [ 51.511293] [] (check_usage) from [] (check_irq_usage+0x54/0xb0) [ 51.519416] [] (check_irq_usage) from [] (__lock_acquire+0xe54/0x1b90) [ 51.528077] [] (__lock_acquire) from [] (lock_acquire+0x9c/0x104) [ 51.536291] [] (lock_acquire) from [] (_raw_spin_lock+0x28/0x38) [ 51.544417] [] (_raw_spin_lock) from [] (find_vmap_area+0x10/0x6c) [ 51.552726] [] (find_vmap_area) from [] (remove_vm_area+0x8/0x6c) [ 51.560935] [] (remove_vm_area) from [] (__vunmap+0x20/0xf8) [ 51.568693] [] (__vunmap) from [] (__arm_iounmap+0x10/0x18) [ 51.576362] [] (__arm_iounmap) from [] (cpdma_ctlr_destroy+0xf0/0x114 [davinci_cpdma]) [ 51.586494] [] (cpdma_ctlr_destroy [davinci_cpdma]) from [] (cpsw_remove+0x48/0x8c [ti_cpsw]) [ 51.597261] [] (cpsw_remove [ti_cpsw]) from [] (platform_drv_remove+0x18/0x1c) [ 51.606659] [] (platform_drv_remove) from [] (__device_release_driver+0x70/0xc8) [ 51.616237] [] (__device_release_driver) from [] (driver_detach+0xb4/0xb8) [ 51.625264] [] (driver_detach) from [] (bus_remove_driver+0x4c/0x90) [ 51.633749] [] (bus_remove_driver) from [] (SyS_delete_module+0x10c/0x198) [ 51.642781] [] (SyS_delete_module) from [] (ret_fast_syscall+0x0/0x48) Signed-off-by: Mugunthan V N Signed-off-by: David S. Miller --- drivers/net/ethernet/ti/davinci_cpdma.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c b/drivers/net/ethernet/ti/davinci_cpdma.c index 32dc28964d2a..657b65bf5cac 100644 --- a/drivers/net/ethernet/ti/davinci_cpdma.c +++ b/drivers/net/ethernet/ti/davinci_cpdma.c @@ -193,12 +193,9 @@ fail: static void cpdma_desc_pool_destroy(struct cpdma_desc_pool *pool) { - unsigned long flags; - if (!pool) return; - spin_lock_irqsave(&pool->lock, flags); WARN_ON(pool->used_desc); if (pool->cpumap) { dma_free_coherent(pool->dev, pool->mem_size, pool->cpumap, @@ -206,7 +203,6 @@ static void cpdma_desc_pool_destroy(struct cpdma_desc_pool *pool) } else { iounmap(pool->iomap); } - spin_unlock_irqrestore(&pool->lock, flags); } static inline dma_addr_t desc_phys(struct cpdma_desc_pool *pool, -- 2.20.1