Hi, I have two Linux boxes connected by a null-modem cable between their serial ports; one box exports a serial console, which the other reads using the minicom program. However, I have noticed that minicom can no longer use the serial console when it is running on a 2.6.25.3 kernel, although it works fine running on a 2.6.24.4 kernel. Specifically, with minicom running on 2.6.25.3, the console does not accept keystrokes although it does receive the boot log from the remote machine. The serial console is being exported by a 2.6.25.3 kernel, and appears to be working correctly. Here is the dmesg log for the kernel hosting minicom, which is using ttyS0: Linux version 2.6.25.3 (chris@xxxxxxxxxxxxxxxxxx) (gcc version 4.1.2 20070925 (Red Hat 4.1.2-33)) #1 Sat May 10 14:41:58 BST 2008 BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) BIOS-e820: 0000000000100000 - 0000000004000000 (usable) BIOS-e820: 00000000fffc0000 - 0000000100000000 (reserved) 64MB LOWMEM available. Scan SMP from c0000000 for 1024 bytes. Scan SMP from c009fc00 for 1024 bytes. Scan SMP from c00f0000 for 65536 bytes. Scan SMP from c009fc00 for 1024 bytes. Entering add_active_range(0, 0, 16384) 0 entries of 256 used Zone PFN ranges: DMA 0 -> 4096 Normal 4096 -> 16384 Movable zone start PFN for each node early_node_map[1] active PFN ranges 0: 0 -> 16384 On node 0 totalpages: 16384 DMA zone: 32 pages used for memmap DMA zone: 0 pages reserved DMA zone: 4064 pages, LIFO batch:0 Normal zone: 96 pages used for memmap Normal zone: 12192 pages, LIFO batch:1 Movable zone: 0 pages used for memmap DMI 2.0 present. Allocating PCI resources starting at 10000000 (gap: 04000000:fbfc0000) Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256 Kernel command line: BOOT_IMAGE=2.6.25.3 ro root=302 mce video=matroxfb:vesa:0x11A No local APIC present or hardware disabled mapped APIC to ffffb000 (01081000) Initializing CPU#0 CPU 0 irqstacks, hard=c0318000 soft=c0317000 PID hash table entries: 256 (order: 8, 1024 bytes) Detected 199.433 MHz processor. Console: colour VGA+ 80x25 console [tty0] enabled Dentry cache hash table entries: 8192 (order: 3, 32768 bytes) Inode-cache hash table entries: 4096 (order: 2, 16384 bytes) Memory: 62272k/65536k available (1376k kernel code, 2852k reserved, 590k data, 156k init, 0k highmem) virtual kernel memory layout: fixmap : 0xfffb9000 - 0xfffff000 ( 280 kB) vmalloc : 0xc4800000 - 0xfffb7000 ( 951 MB) lowmem : 0xc0000000 - 0xc4000000 ( 64 MB) .init : 0xc02ed000 - 0xc0314000 ( 156 kB) .data : 0xc0258156 - 0xc02ebc00 ( 590 kB) .text : 0xc0100000 - 0xc0258156 (1376 kB) Checking if this processor honours the WP bit even in supervisor mode...Ok. CPA: page pool initialized 1 of 1 pages preallocated SLUB: Genslabs=12, HWalign=32, Order=0-1, MinObjects=4, CPUs=1, Nodes=1 Calibrating delay using timer specific routine.. 399.42 BogoMIPS (lpj=1997102) Mount-cache hash table entries: 512 Intel Pentium with F0 0F bug - workaround enabled. Intel old style machine check architecture supported. Intel old style machine check reporting enabled on CPU#0. Compat vDSO mapped to ffffe000. CPU: Intel Pentium MMX stepping 03 Checking 'hlt' instruction... OK. Freeing SMP alternatives: 0k freed net_namespace: 536 bytes NET: Registered protocol family 16 PCI: PCI BIOS revision 2.10 entry at 0xfd2c1, last bus=1 PCI: Using configuration type 1 Setting up standard PCI resources Linux Plug and Play Support v0.97 (c) Adam Belay PnPBIOS: Scanning system for PnP BIOS support... PnPBIOS: Found PnP BIOS installation structure at 0xc00f9f60 PnPBIOS: PnP BIOS version 1.0, entry 0xf0000:0xa060, dseg 0x400 PnPBIOS: 15 nodes reported by PnP BIOS; 15 recorded by driver PCI: Probing PCI hardware PCI: Probing PCI hardware (bus 00) system 00:08: iomem range 0xe8000-0xfffff could not be reserved system 00:08: iomem range 0x0-0x9ffff could not be reserved system 00:08: iomem range 0x100000-0x3ffffff could not be reserved system 00:08: iomem range 0xfffc0000-0xffffffff could not be reserved system 00:08: iomem range 0x0-0x0 could not be reserved system 00:08: iomem range 0x0-0x0 could not be reserved system 00:08: iomem range 0x0-0x0 could not be reserved system 00:08: iomem range 0x0-0x0 could not be reserved system 00:08: iomem range 0x0-0x0 could not be reserved PCI: Bridge: 0000:00:0e.0 IO window: f000-ffff MEM window: 0xff100000-0xff9fffff PREFETCH window: 0x00000000ff000000-0x00000000ff0fffff PCI: Setting latency timer of device 0000:00:0e.0 to 64 NET: Registered protocol family 2 IP route cache hash table entries: 1024 (order: 0, 4096 bytes) TCP established hash table entries: 2048 (order: 2, 16384 bytes) TCP bind hash table entries: 2048 (order: 1, 8192 bytes) TCP: Hash tables configured (established 2048 bind 2048) TCP reno registered apm: BIOS version 1.2 Flags 0x03 (Driver version 1.16ac) VFS: Disk quotas dquot_6.5.1 Dquot-cache hash table entries: 1024 (order 0, 4096 bytes) io scheduler noop registered io scheduler deadline registered (default) pci 0000:00:00.0: Limiting direct PCI/PCI transfers pci 0000:00:07.0: Activating ISA DMA hang workarounds pci 0000:00:0d.0: Boot video device pci 0000:01:05.0: Firmware left e100 interrupts enabled; disabling pci 0000:01:04.0: Firmware left e100 interrupts enabled; disabling pci 0000:00:0f.0: Firmware left e100 interrupts enabled; disabling matroxfb: Matrox Millennium II (PCI) detected PInS memtype = 0 matroxfb: 1280x1024x16bpp (virtual: 1280x1638) matroxfb: framebuffer at 0xFB000000, mapped to 0xc4880000, size 4194304 Console: switching to colour frame buffer device 160x64 fb0: MATROX frame buffer device isapnp: Scanning for PnP cards... pnp: SB audio device quirk - increasing port range isapnp: Card 'Creative ViBRA16C PnP' isapnp: Card 'U.S. Robotics 56K Voice INT' isapnp: 2 Plug & Play cards detected total Generic RTC Driver v1.07 Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A 00:0c: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A serial: probe of 00:0d failed with error -16 serial 01:02.00: activated 01:02.00: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A Uniform Multi-Platform E-IDE driver ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx PIIX3: IDE controller (0x8086:0x7010 rev 0x00) at PCI slot 0000:00:07.1 PIIX3: not 100% native mode: will probe irqs later ide0: BM-DMA at 0xefa0-0xefa7, BIOS settings: hda:PIO, hdb:PIO ide1: BM-DMA at 0xefa8-0xefaf, BIOS settings: hdc:PIO, hdd:PIO Probing IDE interface ide0... hda: WDC AC33200L, ATA DISK drive hdb: WDC AC35100L, ATA DISK drive hda: host max PIO4 wanted PIO255(auto-tune) selected PIO4 hda: MWDMA2 mode selected hdb: host max PIO4 wanted PIO255(auto-tune) selected PIO4 hdb: MWDMA2 mode selected Probing IDE interface ide1... hdc: TOSHIBA CD-ROM XM-6002B, ATAPI CD/DVD-ROM drive hdc: applying conservative PIO "downgrade" hdc: host max PIO4 wanted PIO255(auto-tune) selected PIO2 hdc: MWDMA1 mode selected ide0 at 0x1f0-0x1f7,0x3f6 on irq 14 ide1 at 0x170-0x177,0x376 on irq 15 hda: max request size: 128KiB hda: 6346368 sectors (3249 MB) w/256KiB Cache, CHS=6296/16/63 hda: hda1 hda2 hda3 hdb: max request size: 128KiB hdb: 10085040 sectors (5163 MB) w/256KiB Cache, CHS=10672/15/63 hdb: cache flushes not supported hdb: hdb1 hdb2 hdb3 hdb4 PNP: PS/2 Controller [PNP0303,PNP0f13] at 0x60,0x64 irq 1,12 serio: i8042 KBD port at 0x60,0x64 irq 1 serio: i8042 AUX port at 0x60,0x64 irq 12 mice: PS/2 mouse device common for all mice input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input0 TCP cubic registered NET: Registered protocol family 1 Using IPI Shortcut mode input: ImPS/2 Generic Wheel Mouse as /devices/platform/i8042/serio1/input/input1 kjournald starting. Commit interval 5 seconds EXT3-fs: mounted filesystem with ordered data mode. VFS: Mounted root (ext3 filesystem) readonly. Freeing unused kernel memory: 156k freed Write protecting the kernel text: 1380k Write protecting the kernel read-only data: 452k EXT3 FS on hda2, internal journal Adding 105832k swap on /dev/hdb3. Priority:1 extents:1 across:105832k Adding 105832k swap on /dev/hdb4. Priority:1 extents:1 across:105832k Adding 48376k swap on /dev/hda3. Priority:1 extents:1 across:48376k RPC: Registered udp transport module. RPC: Registered tcp transport module. kjournald starting. Commit interval 5 seconds EXT3 FS on hdb2, internal journal EXT3-fs: mounted filesystem with ordered data mode. kjournald starting. Commit interval 5 seconds EXT3 FS on hdb1, internal journal EXT3-fs: mounted filesystem with ordered data mode. usbcore: registered new interface driver usbfs usbcore: registered new interface driver hub usbcore: registered new device driver usb USB Universal Host Controller Interface driver v3.0 uhci_hcd 0000:00:07.2: UHCI Host Controller uhci_hcd 0000:00:07.2: new USB bus registered, assigned bus number 1 uhci_hcd 0000:00:07.2: irq 11, io base 0x0000ef80 usb usb1: configuration #1 chosen from 1 choice hub 1-0:1.0: USB hub found hub 1-0:1.0: 2 ports detected e100: Intel(R) PRO/100 Network Driver, 3.5.23-k4-NAPI e100: Copyright(c) 1999-2006 Intel Corporation e100: eth0: e100_probe: addr 0xffbeb000, irq 10, MAC addr 00:90:27:76:d0:ec e100: eth1: e100_probe: addr 0xff0fe000, irq 11, MAC addr 00:03:47:3b:29:5c e100: eth2: e100_probe: addr 0xff0ff000, irq 10, MAC addr 00:03:47:3b:29:5d e100: eth0: e100_watchdog: link up, 100Mbps, full-duplex e100: eth2: e100_watchdog: link up, 100Mbps, full-duplex Bridge firewalling registered br0: Dropping NETIF_F_UFO since no NETIF_F_HW_CSUM feature. device eth1 entered promiscuous mode device eth2 entered promiscuous mode br0: port 2(eth2) entering learning state br0: topology change detected, propagating br0: port 2(eth2) entering forwarding state parport_pc 00:0b: reported by Plug and Play BIOS parport0: PC-style at 0x378 (0x778), irq 7, dma 3 [PCSPP,TRISTATE,COMPAT,ECP,DMA] sb16 01:01.00: activated ip_tables: (C) 2000-2006 Netfilter Core Team nf_conntrack version 0.5.0 (1024 buckets, 4096 max) NET: Registered protocol family 10 lo: Disabled Privacy Extensions ADDRCONF(NETDEV_UP): eth1: link is not ready ip6_tables: (C) 2000-2006 Netfilter Core Team prism2usb_init: prism2_usb.o: 0.2.9 Loaded prism2usb_init: dev_info is: prism2_usb usbcore: registered new interface driver prism2_usb process `syslogd' is using obsolete setsockopt SO_BSDCOMPAT warning: `named' uses 32-bit capabilities (legacy support in use) process `named' is using obsolete setsockopt SO_BSDCOMPAT Installing knfsd (copyright (C) 1996 okir@xxxxxxxxxxxx). NFSD: Using /var/lib/nfs/v4recovery as the NFSv4 state recovery directory NFSD: starting 90-second grace period hdc: ATAPI 16X CD-ROM drive, 256kB Cache Uniform CD-ROM driver Revision: 3.20 input: PC Speaker as /devices/platform/pcspkr/input/input2 Cheers, Chris __________________________________________________________ Sent from Yahoo! Mail. A Smarter Email http://uk.docs.yahoo.com/nowyoucan.html -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html