------- Blind-Carbon-Copy X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.1 From: Keith Owens <kaos@xxxxxxxxxx> To: linux-kernel@xxxxxxxxxxxxxxx cc: len.brown@xxxxxxxxx Subject: PNPACPI probes serial twice, messes up serial console Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 20 Mar 2007 17:46:46 +1100 Message-ID: <17887.1174373206@xxxxxxxxxxxxxxxxxxxxxx> Dell SC1425 x86_64 running in i386 mode (the problem also occurs in x86_64 mode). Kernel 2.6.21-rc4, gcc 4.1.0. Config extract at end. Booting with 'console=tty console=ttyS0,9600'. The serial console on ttyS0 (0x3f8, irq 4) is probed twice, once from serial8250_init() and again from serial_pnp_probe(). The serial console output is correct until the second probe (from PNP) gets to these lines in serial8250_config_port() if (flags & UART_CONFIG_TYPE) autoconfig(up, probeflags); After the call to autoconfig(), the serial console starts printing NUL characters instead of the console output. The number of NUL characters corresponds closely with the number of characters written to the VT console, IOW it outputs each serial character as NUL instead of the correct character. When the kernel boots /sbin/init, the console resets to printing normal characters. AFAICT, the second probe of the UART is doing something nasty to the hardware. This is not a recent problem, I can reproduce the problem on 2.6.16. Booting with pnpacpi=off removes the problem, but that supresses all the PNPACPI code, not just the second probe of the serial devices. Should pnpacpi probe and setup the serial devices even when thay have already been setup? Or this is something strange about the UART in this particular box? FWIW, the serial console is plugged into a serial to USB converter (pl2303), my laptop has no serial ports. That should not make a difference, but just in case it does ... Config extract: X86_32=y GENERIC_TIME=y CLOCKSOURCE_WATCHDOG=y GENERIC_CLOCKEVENTS=y GENERIC_CLOCKEVENTS_BROADCAST=y LOCKDEP_SUPPORT=y STACKTRACE_SUPPORT=y SEMAPHORE_SLEEPERS=y X86=y MMU=y ZONE_DMA=y GENERIC_ISA_DMA=y GENERIC_IOMAP=y GENERIC_BUG=y GENERIC_HWEIGHT=y ARCH_MAY_HAVE_PC_FDC=y DMI=y DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config" EXPERIMENTAL=y LOCK_KERNEL=y INIT_ENV_ARG_LIMIT=32 LOCALVERSION="-i386-kaos" LOCALVERSION_AUTO=y SWAP=y SYSVIPC=y SYSVIPC_SYSCTL=y POSIX_MQUEUE=y IKCONFIG=y IKCONFIG_PROC=y SYSFS_DEPRECATED=y CC_OPTIMIZE_FOR_SIZE=y SYSCTL=y EMBEDDED=y SYSCTL_SYSCALL=y KALLSYMS=y KALLSYMS_ALL=y HOTPLUG=y PRINTK=y BUG=y ELF_CORE=y BASE_FULL=y FUTEX=y EPOLL=y SHMEM=y SLAB=y VM_EVENT_COUNTERS=y RT_MUTEXES=y BASE_SMALL=0 MODULES=y MODULE_UNLOAD=y KMOD=y STOP_MACHINE=y BLOCK=y LBD=y LSF=y IOSCHED_NOOP=y IOSCHED_AS=y IOSCHED_DEADLINE=y IOSCHED_CFQ=y DEFAULT_DEADLINE=y DEFAULT_IOSCHED="deadline" TICK_ONESHOT=y HIGH_RES_TIMERS=y SMP=y X86_PC=y MPENTIUM4=y X86_CMPXCHG=y X86_L1_CACHE_SHIFT=7 RWSEM_XCHGADD_ALGORITHM=y GENERIC_CALIBRATE_DELAY=y X86_WP_WORKS_OK=y X86_INVLPG=y X86_BSWAP=y X86_POPAD_OK=y X86_CMPXCHG64=y X86_GOOD_APIC=y X86_INTEL_USERCOPY=y X86_USE_PPRO_CHECKSUM=y X86_TSC=y HPET_TIMER=y HPET_EMULATE_RTC=y NR_CPUS=8 SCHED_SMT=y PREEMPT_NONE=y X86_LOCAL_APIC=y X86_IO_APIC=y X86_MCE=y X86_MCE_NONFATAL=y X86_MCE_P4THERMAL=y MICROCODE=m MICROCODE_OLD_INTERFACE=y X86_MSR=m X86_CPUID=m HIGHMEM4G=y VMSPLIT_3G=y PAGE_OFFSET=0xC0000000 HIGHMEM=y ARCH_FLATMEM_ENABLE=y ARCH_SPARSEMEM_ENABLE=y ARCH_SELECT_MEMORY_MODEL=y ARCH_POPULATES_NODE_MAP=y SELECT_MEMORY_MODEL=y FLATMEM_MANUAL=y FLATMEM=y FLAT_NODE_MEM_MAP=y SPARSEMEM_STATIC=y SPLIT_PTLOCK_CPUS=4 ZONE_DMA_FLAG=1 MTRR=y IRQBALANCE=y HZ_250=y HZ=250 PHYSICAL_START=0x100000 PHYSICAL_ALIGN=0x100000 COMPAT_VDSO=y ARCH_ENABLE_MEMORY_HOTPLUG=y PM=y ACPI=y ACPI_PROCFS=y ACPI_BUTTON=m ACPI_FAN=m ACPI_PROCESSOR=m ACPI_BLACKLIST_YEAR=0 ACPI_EC=y ACPI_POWER=y ACPI_SYSTEM=y PCI=y PCI_GOANY=y PCI_BIOS=y PCI_DIRECT=y PCI_MMCONFIG=y PCIEPORTBUS=y PCIEAER=y PCI_MSI=y HT_IRQ=y ISA_DMA_API=y BINFMT_ELF=y BINFMT_MISC=m NET=y PACKET=y PACKET_MMAP=y UNIX=y XFRM=y INET=y IP_MULTICAST=y IP_ADVANCED_ROUTER=y ASK_IP_FIB_HASH=y IP_FIB_HASH=y IP_ROUTE_MULTIPATH=y IP_ROUTE_VERBOSE=y SYN_COOKIES=y INET_XFRM_MODE_BEET=y INET_DIAG=y INET_TCP_DIAG=y TCP_CONG_CUBIC=y DEFAULT_TCP_CONG="cubic" NETFILTER=y NETFILTER_NETLINK=m NETFILTER_NETLINK_LOG=m NETFILTER_XTABLES=y NETFILTER_XT_TARGET_CLASSIFY=m NETFILTER_XT_TARGET_MARK=m NETFILTER_XT_MATCH_COMMENT=m NETFILTER_XT_MATCH_DCCP=m NETFILTER_XT_MATCH_ESP=m NETFILTER_XT_MATCH_LENGTH=m NETFILTER_XT_MATCH_LIMIT=m NETFILTER_XT_MATCH_MAC=m NETFILTER_XT_MATCH_MARK=m NETFILTER_XT_MATCH_MULTIPORT=m NETFILTER_XT_MATCH_PKTTYPE=m NETFILTER_XT_MATCH_QUOTA=m NETFILTER_XT_MATCH_REALM=m NETFILTER_XT_MATCH_SCTP=m NETFILTER_XT_MATCH_STATISTIC=m NETFILTER_XT_MATCH_TCPMSS=m IP_NF_IPTABLES=y IP_NF_MATCH_IPRANGE=m IP_NF_MATCH_TOS=m IP_NF_MATCH_RECENT=m IP_NF_MATCH_ECN=m IP_NF_MATCH_AH=m IP_NF_MATCH_TTL=m IP_NF_MATCH_OWNER=m IP_NF_MATCH_ADDRTYPE=m IP_NF_FILTER=y IP_NF_TARGET_REJECT=y IP_NF_TARGET_ULOG=y VLAN_8021Q=y NET_CLS_ROUTE=y STANDALONE=y PREVENT_FIRMWARE_BUILD=y FW_LOADER=m CONNECTOR=m PNP=y PNP_DEBUG=y PNPACPI=y BLK_DEV_FD=m BLK_DEV_LOOP=m IDE=m IDE_MAX_HWIFS=4 BLK_DEV_IDE=m BLK_DEV_IDEDISK=m IDEDISK_MULTI_MODE=y BLK_DEV_IDECD=m IDE_TASK_IOCTL=y BLK_DEV_IDEPCI=y IDEPCI_SHARE_IRQ=y BLK_DEV_IDEDMA_PCI=y IDEDMA_PCI_AUTO=y BLK_DEV_PIIX=m BLK_DEV_IDEDMA=y IDEDMA_AUTO=y RAID_ATTRS=m SCSI=y SCSI_PROC_FS=y BLK_DEV_SD=y CHR_DEV_SG=y SCSI_CONSTANTS=y SCSI_SPI_ATTRS=y SCSI_3W_9XXX=y SCSI_SYM53C8XX_2=y SCSI_SYM53C8XX_DMA_ADDRESSING_MODE=1 SCSI_SYM53C8XX_DEFAULT_TAGS=16 SCSI_SYM53C8XX_MAX_TAGS=64 SCSI_SYM53C8XX_MMIO=y ATA=y ATA_PIIX=y SATA_ACPI=y MD=y BLK_DEV_MD=y MD_RAID1=y BLK_DEV_DM=y DM_SNAPSHOT=y DM_MIRROR=y NETDEVICES=y DUMMY=m BONDING=m E1000=y E1000_NAPI=y SKY2=m NETCONSOLE=m NETPOLL=y NET_POLL_CONTROLLER=y INPUT=y INPUT_KEYBOARD=y KEYBOARD_ATKBD=y SERIO=y SERIO_I8042=y SERIO_LIBPS2=y SERIO_RAW=m VT=y VT_CONSOLE=y HW_CONSOLE=y SERIAL_8250=y SERIAL_8250_CONSOLE=y SERIAL_8250_PCI=m SERIAL_8250_PNP=y SERIAL_8250_NR_UARTS=4 SERIAL_8250_RUNTIME_UARTS=4 SERIAL_CORE=y SERIAL_CORE_CONSOLE=y UNIX98_PTYS=y IPMI_HANDLER=y IPMI_PANIC_EVENT=y IPMI_DEVICE_INTERFACE=y IPMI_SI=y IPMI_WATCHDOG=y IPMI_POWEROFF=m WATCHDOG=y SOFT_WATCHDOG=m I8XX_TCO=y NVRAM=m RTC=y HPET=y HPET_MMAP=y I2C=y I2C_CHARDEV=m I2C_ALGOBIT=m I2C_I801=y SENSORS_EEPROM=m HWMON=y VGA_CONSOLE=y DUMMY_CONSOLE=y HID=y USB_ARCH_HAS_HCD=y USB_ARCH_HAS_OHCI=y USB_ARCH_HAS_EHCI=y USB=y USB_DEVICEFS=y USB_EHCI_HCD=y USB_STORAGE=m USB_HID=y USB_MON=y USB_SERIAL=m USB_SERIAL_GENERIC=y USB_SERIAL_PL2303=m EDAC=y EDAC_MM_EDAC=y EDAC_E752X=y EDAC_POLL=y EXT2_FS=m EXT3_FS=y JBD=y XFS_FS=y INOTIFY=y INOTIFY_USER=y ISO9660_FS=m JOLIET=y UDF_FS=m UDF_NLS=y FAT_FS=m MSDOS_FS=m VFAT_FS=m FAT_DEFAULT_CODEPAGE=850 FAT_DEFAULT_IOCHARSET="iso8859-1" PROC_FS=y PROC_KCORE=y PROC_SYSCTL=y SYSFS=y TMPFS=y RAMFS=y NFS_FS=y NFS_V3=y NFSD=y NFSD_V3=y LOCKD=y LOCKD_V4=y EXPORTFS=y NFS_COMMON=y SUNRPC=y MSDOS_PARTITION=y NLS=m NLS_DEFAULT="iso8859-15" NLS_CODEPAGE_437=m NLS_CODEPAGE_850=m NLS_CODEPAGE_865=m NLS_ASCII=m NLS_ISO8859_1=m NLS_ISO8859_15=m NLS_UTF8=m TRACE_IRQFLAGS_SUPPORT=y ENABLE_MUST_CHECK=y MAGIC_SYSRQ=y DEBUG_KERNEL=y LOG_BUF_SHIFT=16 DETECT_SOFTLOCKUP=y DEBUG_SPINLOCK=y DEBUG_MUTEXES=y DEBUG_BUGVERBOSE=y FORCED_INLINING=y DEBUG_STACKOVERFLOW=y DEBUG_RODATA=y X86_FIND_SMP_CONFIG=y X86_MPPARSE=y DOUBLEFAULT=y KDB=y KDB_MODULES=y KDB_CONTINUE_CATASTROPHIC=0 BITREVERSE=y CRC32=y PLIST=y HAS_IOMEM=y HAS_IOPORT=y GENERIC_HARDIRQS=y GENERIC_IRQ_PROBE=y GENERIC_PENDING_IRQ=y X86_SMP=y X86_HT=y X86_BIOS_REBOOT=y X86_TRAMPOLINE=y KTIME_SCALAR=y ------- End of Blind-Carbon-Copy - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
