On Thu, Aug 04, 2016 at 06:59:30AM +0200, Greg Kroah-Hartman wrote: > On Wed, Aug 03, 2016 at 09:06:25AM +0200, Ladislav Michl wrote: > > Yes, also was lacking proper description and signoff. So, I'm considering > > ioctls based approach okay, although that question (the only one I really > > had) was never answered. > > > > After re-reading specifications [*] I decided to allow arbitrary MsgID > > selection, as USB488 adds MsgID=TRIGGER (128) and other subclass > > specifications may add other values. > > > > [*] http://www.usb.org/developers/docs/devclass_docs/USBTMC_1_006a.zip > > > > After sorting out all eventual objections, patch bellow will be turned > > into proper one. > > Looks reasonable to me. After all, it is not that reasonable. Spec does not define anything like EOM or TermCharEnabled bits in bmTransferAttributes nor TermChar field in vendor specific messages - usbtmc_read and usbtmc_write are using these fields when concatenating usb transfers. I'll need to think a bit more about it... Meanwhile, there's a small race condition, which needs to be fixed first. When device is disconnected there's a chance usbtmc_read tries to lock already destroyd mutex, see bellow. Fix will come later in separate patch. thank you, ladis Unable to handle kernel NULL pointer dereference at virtual address 00000008 pgd = cd55c000 [00000008] *pgd=8d52e831, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] ARM Modules linked in: usbtmc ppp_deflate bsd_comp ppp_async crc_ccitt ppp_generic slhc cpufreq_dt udlfb syscopyarea sysfillrect sysimgblt fb_sys_fops omap_aes omap_sham crypto_engine omap_mailbox option cdc_acm usb_wwan usbserial usb_storage scsi_mod CPU: 0 PID: 205 Comm: tvm3 Tainted: G W 4.6.0 #1 Hardware name: Generic OMAP36xx (Flattened Device Tree) task: ce2ae700 ti: ce1e2000 task.ti: ce1e2000 PC is at __bfs+0x11c/0x23c LR is at warn_slowpath_null+0x1c/0x24 pc : [<c014fb48>] lr : [<c012825c>] psr: 60010093 sp : ce1e3d30 ip : 00000000 fp : c0a76388 r10: 00000000 r9 : ce1e3d74 r8 : c0a72398 r7 : ce1e3d70 r6 : c0a76388 r5 : c0c433f4 r4 : c0a72398 r3 : 00000200 r2 : e55130aa r1 : c0951cd0 r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 8d55c019 DAC: 00000051 Process tvm3 (pid: 205, stack limit = 0xce1e2210) Stack: (0xce1e3d30 to 0xce1e4000) 3d20: ce1e4000 c014f928 00000000 e55130aa 3d40: 00000003 00000001 ce2aeab0 ce2ae700 c073ceee 00000000 00000000 c0151090 3d60: 00000000 c015113c 00000000 c0c99af8 ce2aeab0 c010adc4 c0c4333c c0c432fc 3d80: 00000000 00000000 00000000 ce1e3fa8 c01074a0 00000000 00000072 00000001 3da0: 00000002 ce2aeab0 c0603f60 ce2ae700 00000000 c0151cc4 ce2ae700 00000000 3dc0: 3c48dade 0000001e 00000001 ce103300 ce2ae700 c0152c88 00000000 ce2a0030 3de0: ce2aeab0 00000000 00000100 c0151fcc ce2ae700 00000001 c01c6a8c 001a9ca0 3e00: ce800000 c0152174 cd4e5980 a0010013 cfc7cf7c c01c6a8c 00000000 ce245420 3e20: 00000003 00000000 60010013 00000001 c10ed4ec ce2ae700 ce1e2000 00000000 3e40: 00000100 c015470c 00000001 00000000 00000000 bf14d88c 00000000 00000000 3e60: cd5a5a60 bf14d840 ce20c800 c05a8c94 00000001 00000000 bf14d88c a0010013 3e80: c0107644 c0152174 ce20c800 ce800300 cd5a5a10 bf14d840 ce20c800 c10f5cc8 3ea0: c0107644 ce1e2000 00000000 bf14d88c ce2aeab0 00000001 00000051 00000000 3ec0: b2afeb60 cd5a5a60 ce1e3f88 00000001 000670f1 c0f3c608 00000000 cd5a7a00 3ee0: bf14d840 ce1e3f88 b2afeb60 c0107644 ce1e2000 00000000 00000000 c01cc0b8 3f00: 00000000 c02e34f0 00000000 00000000 00000c00 00000000 cd5a7a00 00000100 3f20: 00000000 c01ccb40 00004000 c0943184 00000038 00000000 00000000 b2afeb60 3f40: cd5a7a00 ce1e3f88 b2afeb60 b2afeb60 cd5a7a00 ce1e3f88 b2afeb60 c01ccc58 3f60: cd5a7a00 b2afeb60 00000100 cd5a7a00 cd5a7a01 00000100 b2afeb60 c0107644 3f80: ce1e2000 c01cd834 00000c00 00000000 00000100 0000000e ffffffff 000a8050 3fa0: 00000003 c01074a0 0000000e ffffffff 0000000e b2afeb60 00000100 00000000 3fc0: 0000000e ffffffff 000a8050 00000003 000a8054 000a67cc 0008e3b4 00000000 3fe0: 00000000 b2afeb40 00000000 b6d48b60 80010030 0000000e 8fef6861 8fef6c61 [<c014fb48>] (__bfs) from [<c015113c>] (check_usage_backwards+0xac/0x140) [<c015113c>] (check_usage_backwards) from [<c0151cc4>] (mark_lock+0x36c/0x618) [<c0151cc4>] (mark_lock) from [<c0152c88>] (__lock_acquire+0x880/0x1b88) [<c0152c88>] (__lock_acquire) from [<c015470c>] (lock_acquire+0x70/0x90) [<c015470c>] (lock_acquire) from [<c05a8c94>] (mutex_lock_nested+0x3c/0x314) [<c05a8c94>] (mutex_lock_nested) from [<bf14d88c>] (usbtmc_read+0x4c/0x4e8 [usbtmc]) [<bf14d88c>] (usbtmc_read [usbtmc]) from [<c01cc0b8>] (__vfs_read+0x20/0xcc) [<c01cc0b8>] (__vfs_read) from [<c01ccc58>] (vfs_read+0x84/0xec) [<c01ccc58>] (vfs_read) from [<c01cd834>] (SyS_read+0x40/0x80) [<c01cd834>] (SyS_read) from [<c01074a0>] (ret_fast_syscall+0x0/0x1c) Code: e30013af e58d200c ebff61be e59d200c (e59a1008) ---[ end trace dd5c876458afcc20 ]--- Kernel panic - not syncing: Fatal exception -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
