From mboxrd@z Thu Jan 1 00:00:00 1970 From: dyoung@redhat.com (Dave Young) Date: Sat, 2 Jan 2016 15:02:31 +0800 Subject: bbb kexec bug: Unhandled fault external abort on non-linefetch (0x1028) at 0xfa1ac140 In-Reply-To: <568127FE.3010001@ti.com> References: <20151227073840.GC23608@dhcp-128-65.nay.redhat.com> <20151228071809.GA20621@dhcp-128-65.nay.redhat.com> <568127FE.3010001@ti.com> Message-ID: <20160102070231.GA23855@dhcp-128-65.nay.redhat.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, Grygorii Thanks fot your reply. On 12/28/15 at 02:15pm, Grygorii Strashko wrote: > On 12/28/2015 09:18 AM, Dave Young wrote: > > On 12/27/15 at 03:38pm, Dave Young wrote: > >> Here is what I get when I test kdump on Beagle bone black: > >> > >> Added a printk line at the begin of function omap_gpio_rmw: > >> printk("########## %lx, %x, %x\n", base, reg, mask); > >> > >> Any hints how to fix it? I tried call the machine_kexec_mask_interrupts > >> at runtime kernel also panics so it may not limit to kdump case. > >> > >> [ 66.340168] ########## fa1ac000, 140, 1 > >> [ 66.344456] Unhandled fault: external abort on non-linefetch (0x1028) at 0xfa1ac140 > >> [ 66.352142] pgd = dd9f0000 > > [...] > > >> [ 66.727278] [] (omap_set_gpio_triggering) from [] (omap_gpio_mask_irq+0x29/0x34) > > Usually such back-trace means that you are trying to access HW > which is disabled (powered off) already. Or this HW IP has never been enabled. It is possible, but how to detect such disabled gpio in this for_each_irq_desc loop? I tried below, it works for me but I'm not sure if it is a right fix. --- arch/arm/kernel/machine_kexec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- linux.orig/arch/arm/kernel/machine_kexec.c +++ linux/arch/arm/kernel/machine_kexec.c @@ -106,7 +106,7 @@ static void machine_kexec_mask_interrupt if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data)) chip->irq_eoi(&desc->irq_data); - if (chip->irq_mask) + if ((chip->irq_mask) && !irqd_irq_masked(&desc->irq_data)) chip->irq_mask(&desc->irq_data); if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data)) > > >> [ 66.736457] [] (omap_gpio_mask_irq) from [] (machine_crash_shutdown+0xb9/0x104) > >> [ 66.745551] [] (machine_crash_shutdown) from [] (crash_kexec+0x35/0x68) > >> [ 66.753942] [] (crash_kexec) from [] (die+0x1b9/0x390) > >> [ 66.760859] [] (die) from [] (__do_kernel_fault.part.0+0x4f/0x1cc) > >> [ 66.768824] [] (__do_kernel_fault.part.0) from [] (do_page_fault+0x155/0x29c) > >> [ 66.777740] [] (do_page_fault) from [] (do_DataAbort+0x2f/0x88) > >> [ 66.785432] [] (do_DataAbort) from [] (__dabt_svc+0x3b/0x80) > >> [ 66.792858] Exception stack(0xddc39e58 to 0xddc39ea0) > >> [ 66.797929] 9e40: 00000063 df93647c > >> [ 66.806144] 9e60: 1f26a000 00000000 00000001 00000063 00000007 c0702e3c 00000000 ddc38000 > >> [ 66.814359] 9e80: 00000000 7f70d614 00000030 ddc39ea8 c021e54b c021e54c 600e0033 ffffffff > >> [ 66.822575] [] (__dabt_svc) from [] (sysrq_handle_crash+0x18/0x1c) > >> [ 66.830530] [] (sysrq_handle_crash) from [] (__handle_sysrq+0x79/0x10c) > >> [ 66.838919] [] (__handle_sysrq) from [] (write_sysrq_trigger+0x45/0x50) > >> [ 66.847310] [] (write_sysrq_trigger) from [] (proc_reg_write+0x43/0x68) > >> [ 66.855700] [] (proc_reg_write) from [] (__vfs_write+0xf/0x8c) > >> [ 66.863304] [] (__vfs_write) from [] (vfs_write+0x5f/0x128) > >> [ 66.870646] [] (vfs_write) from [] (SyS_write+0x2b/0x68) > >> [ 66.877729] [] (SyS_write) from [] (ret_fast_syscall+0x1/0x4c) > >> [ 66.885332] Code: 443c 4643 f6a9 f9a1 (6823) 0732 > >> [ 66.890145] ---[ end trace 5a39094ece4dc200 ]--- > >> [ 66.894782] Kernel panic - not syncing: Fatal exception > >> [ 66.900033] ---[ end Kernel panic - not syncing: Fatal exception > >> > > > -- > regards, > -grygorii Thanks Dave