From 41314fea2ffb6dc716b7e698a47c68b329602fc0 Mon Sep 17 00:00:00 2001 From: Russell King - ARM Linux Date: Wed, 16 Oct 2013 13:45:15 +0100 Subject: [PATCH] usb/chipidea: fix oops on memory allocation failure When CMA fails to initialize in v3.12-rc4, the chipidea driver oopses the kernel while trying to remove and put the HCD which doesn't exist: WARNING: CPU: 0 PID: 6 at /home/rmk/git/linux-rmk/arch/arm/mm/dma-mapping.c:511 __dma_alloc+0x200/0x240() coherent pool not initialised! Modules linked in: CPU: 0 PID: 6 Comm: kworker/u2:0 Tainted: G W 3.12.0-rc4+ #56 Workqueue: deferwq deferred_probe_work_func Backtrace: [] (dump_backtrace+0x0/0x10c) from [] (show_stack+0x18/0x1c) r6:c05fd9cc r5:000001ff r4:00000000 r3:df86ad00 [] (show_stack+0x0/0x1c) from [] (dump_stack+0x70/0x8c) [] (dump_stack+0x0/0x8c) from [] (warn_slowpath_common+0x6c/0x8c) r4:df883a60 r3:df86ad00 [] (warn_slowpath_common+0x0/0x8c) from [] (warn_slowpath_fmt+0x38/0x40) r8:ffffffff r7:00001000 r6:c083b808 r5:00000000 r4:df2efe80 [] (warn_slowpath_fmt+0x0/0x40) from [] (__dma_alloc+0x200/0x240) r3:00000000 r2:c05fda00 [] (__dma_alloc+0x0/0x240) from [] (arm_dma_alloc+0x88/0xa0) [] (arm_dma_alloc+0x0/0xa0) from [] (ehci_setup+0x1f4/0x438) [] (ehci_setup+0x0/0x438) from [] (usb_add_hcd+0x18c/0x664) [] (usb_add_hcd+0x0/0x664) from [] (host_start+0xf0/0x180) [] (host_start+0x0/0x180) from [] (ci_hdrc_probe+0x360/0x670 ) r6:df2ef410 r5:00000000 r4:df2c3010 r3:c03e8904 [] (ci_hdrc_probe+0x0/0x670) from [] (platform_drv_probe+0x20/0x24) [] (platform_drv_probe+0x0/0x24) from [] (driver_probe_device+0x9c/0x234) ... ---[ end trace c88ccaf3969e8422 ]--- Unable to handle kernel NULL pointer dereference at virtual address 00000028 pgd = c0004000 [00000028] *pgd=00000000 Internal error: Oops: 17 [#1] SMP ARM Modules linked in: CPU: 0 PID: 6 Comm: kworker/u2:0 Tainted: G W 3.12.0-rc4+ #56 Workqueue: deferwq deferred_probe_work_func task: df86ad00 ti: df882000 task.ti: df882000 PC is at usb_remove_hcd+0x10/0x150 LR is at host_stop+0x1c/0x3c pc : [] lr : [] psr: 60000013 sp : df883b50 ip : df883b78 fp : df883b74 r10: c11f4c54 r9 : c0836450 r8 : df30c400 r7 : fffffff4 r6 : df2ef410 r5 : 00000000 r4 : df2c3010 r3 : 00000000 r2 : 00000000 r1 : df86b0a0 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c53c7d Table: 2f29404a DAC: 00000015 Process kworker/u2:0 (pid: 6, stack limit = 0xdf882240) Stack: (0xdf883b50 to 0xdf884000) ... Backtrace: [] (usb_remove_hcd+0x0/0x150) from [] (host_stop+0x1c/0x3c) r6:df2ef410 r5:00000000 r4:df2c3010 [] (host_stop+0x0/0x3c) from [] (ci_hdrc_host_destroy+0x1c/0x20) r5:00000000 r4:df2c3010 [] (ci_hdrc_host_destroy+0x0/0x20) from [] (ci_hdrc_probe+0x3ac/0x670) [] (ci_hdrc_probe+0x0/0x670) from [] (platform_drv_probe+0x20/0x24) [] (platform_drv_probe+0x0/0x24) from [] (driver_probe_device+0x9c/0x234) [] (driver_probe_device+0x0/0x234) from [] (__device_attach+0x44/0x48) ... ---[ end trace c88ccaf3969e8423 ]--- Fix this so at least we can continue booting and get to a shell prompt. Signed-off-by: Russell King Tested-by: Russell King Signed-off-by: Greg Kroah-Hartman --- drivers/usb/chipidea/host.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c index 6f96795dd20c..64d7a6d9a1ad 100644 --- a/drivers/usb/chipidea/host.c +++ b/drivers/usb/chipidea/host.c @@ -100,8 +100,10 @@ static void host_stop(struct ci_hdrc *ci) { struct usb_hcd *hcd = ci->hcd; - usb_remove_hcd(hcd); - usb_put_hcd(hcd); + if (hcd) { + usb_remove_hcd(hcd); + usb_put_hcd(hcd); + } if (ci->platdata->reg_vbus) regulator_disable(ci->platdata->reg_vbus); } -- 2.11.0