* Pavel Machek <pavel@xxxxxx> [180308 14:31]: > Hi! > > I'm getting this warning... Has anyone seen/debugged that before? > Unfortunately the backtrace does not seem to be too useful :-(. Adding Suman to Cc, as it points to arm_iommu_release_mapping(). Regards, Tony > [ 0.000000] Booting Linux on physical CPU 0x0 > [ 0.000000] Linux version 4.16.0-rc3-next-20180302 (pavel@duo) (gcc > version 4.7.2 (GC > C)) #70 Fri Mar 2 10:16:00 CET 2018 > [ 0.000000] CPU: ARMv7 Processor [411fc083] revision 3 (ARMv7), > cr=10c5387d > [ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT > nonaliasing instruction cac > ... > [ 1.244140] omap3isp 480bc000.isp: 480bc000.isp supply vdd-csiphy2 > not found, using d > ummy regulator > [ 1.254089] omap3isp 480bc000.isp: Revision 2.0 found > [ 1.260009] omap-iommu 480bd400.mmu: 480bd400.mmu: version 1.1 > [ 1.266693] ------------[ cut here ]------------ > [ 1.271606] WARNING: CPU: 0 PID: 1 at lib/refcount.c:187 > refcount_sub_and_test+0x94/0xa8 > [ 1.280181] refcount_t: underflow; use-after-free. > [ 1.285247] Modules linked in: > [ 1.288482] CPU: 0 PID: 1 Comm: swapper Not tainted > 4.16.0-rc3-next-20180302 #70 > [ 1.296295] Hardware name: Nokia RX-51 board > [ 1.300811] [<c010d6cc>] (unwind_backtrace) from [<c010b560>] > (show_stack+0x10/0x14) > [ 1.309020] [<c010b560>] (show_stack) from [<c0127dec>] > (__warn+0xe8/0x110) > [ 1.316375] [<c0127dec>] (__warn) from [<c0127edc>] > (warn_slowpath_fmt+0x38/0x48) > [ 1.324310] [<c0127edc>] (warn_slowpath_fmt) from [<c034e630>] > (refcount_sub_and_test+0x94/0xa8) > [ 1.333557] [<c034e630>] (refcount_sub_and_test) from [<c01109a8>] > (arm_iommu_release_mapping+0x18/0x2c) > [ 1.343597] [<c01109a8>] (arm_iommu_release_mapping) from > [<c041752c>] (driver_probe_device+0x24c/0x314) > [ 1.353637] [<c041752c>] (driver_probe_device) from [<c04176a0>] > (__driver_attach+0xac/0xb0) > [ 1.362548] [<c04176a0>] (__driver_attach) from [<c0415b94>] > (bus_for_each_dev+0x58/0x7c) > [ 1.371185] [<c0415b94>] (bus_for_each_dev) from [<c0416a14>] > (bus_add_driver+0xe0/0x1f0) > [ 1.379852] [<c0416a14>] (bus_add_driver) from [<c0417f10>] > (driver_register+0x78/0xf4) > [ 1.388305] [<c0417f10>] (driver_register) from [<c010257c>] > (do_one_initcall+0x3c/0x16c) > [ 1.396972] [<c010257c>] (do_one_initcall) from [<c0b00d5c>] > (kernel_init_freeable+0xf8/0x1c4) > [ 1.406066] [<c0b00d5c>] (kernel_init_freeable) from [<c071640c>] > (kernel_init+0x8/0x108) > [ 1.414703] [<c071640c>] (kernel_init) from [<c01010e8>] > (ret_from_fork+0x14/0x2c) > [ 1.422698] Exception stack(0xce049fb0 to 0xce049ff8) > [ 1.428039] 9fa0: 00000000 > 00000000 00000000 00000000 > [ 1.436676] 9fc0: 00000000 00000000 00000000 00000000 00000000 > 00000000 00000000 00000000 > [ 1.445312] 9fe0: 00000000 00000000 00000000 00000000 00000013 > 00000000 > [ 1.452270] ---[ end trace dcb3a72772bbfe7a ]--- > [ 1.459045] ti-soc-thermal 48002524.bandgap: This OMAP thermal > sensor is unreliable. You've been warned > [ 1.469055] ti-soc-thermal 48002524.bandgap: Non-trimmed BGAP, Temp > not accurate > [ 1.476898] ti-soc-thermal 48002524.bandgap: thermal zone device is > NULL > [ 1.485198] omap_wdt: OMAP Watchdog Timer Rev 0x31: initial timeout > 60 sec > [ 1.495208] omap_hsmmc 4809c000.mmc: GPIO lookup for consumer cd > > -- > (english) http://www.livejournal.com/~pavelmachek > (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html