Please take this patch to drivers/char/serial.c. It fixes a problem I was
having where the kernel would lock up solidly (infinite loop in serial.c).
The problem is that startup() was being called multiple times, creating
a cycle in the IRQ chain. This was happening under vanilla 2.1.130 after
booting directly to single user mode. The lock-up would occur when I ran
'kermit -l /dev/ttyS1 -b 38400 -c' as any other user than root. For root,
startup() would only be called once.
This patch simply makes sure that startup() does not insert an entry into
the IRQ chain if it is already there, as well as perform a more cautious
scan of the IRQ chain in the function where I discovered the problem.
(my .config follows the diff)
-Truxton
diff -u old/serial.c new/serial.c
--- old/serial.c Fri Dec 4 01:09:50 1998
+++ new/serial.c Fri Dec 4 01:14:12 1998
@@ -903,6 +903,11 @@
if (info->timeout < timeout)
timeout = info->timeout;
info = info->next_port;
+ if(info==IRQ_ports[irq])
+ {
+ printk("Uh-Oh! cycle detected in IRQ %d chain (serial.c)\n",irq) ;
+ info=0 ;
+ }
}
if (!irq)
timeout = timeout / 2;
@@ -919,6 +924,8 @@
#ifdef CONFIG_SERIAL_MANY_PORTS
unsigned short ICP;
#endif
+ struct async_struct *p ;
+ int already_in_chain ;
page = get_free_page(GFP_KERNEL);
if (!page)
@@ -1019,11 +1026,28 @@
/*
* Insert serial port into IRQ chain.
*/
- info->prev_port = 0;
- info->next_port = IRQ_ports[state->irq];
- if (info->next_port)
- info->next_port->prev_port = info;
- IRQ_ports[state->irq] = info;
+ already_in_chain=0 ;
+ for(p=IRQ_ports[state->irq];p!=NULL;)
+ {
+ if(p==info)
+ already_in_chain=1 ;
+ p=p->next_port ;
+ if(p==IRQ_ports[state->irq])
+ {
+ printk("Uh-Oh! cycle detected in IRQ %d chain (serial.c)\n",state->irq) ;
+ p=0 ;
+ }
+ }
+ if(already_in_chain)
+ printk("serial.c: startup: I refuse to create a cycle in IRQ chain %d\n",state->irq) ;
+ else
+ {
+ info->prev_port = 0;
+ info->next_port = IRQ_ports[state->irq];
+ if (info->next_port)
+ info->next_port->prev_port = info;
+ IRQ_ports[state->irq] = info;
+ }
figure_IRQ_timeout(state->irq);
/*
==================================================================
#
# Automatically generated make config: don't edit
#
#
# Code maturity level options
#
# CONFIG_EXPERIMENTAL is not set
#
# Processor type and features
#
# CONFIG_M386 is not set
# CONFIG_M486 is not set
CONFIG_M586=y
# CONFIG_M686 is not set
# CONFIG_MATH_EMULATION is not set
#
# Loadable module support
#
CONFIG_MODULES=y
# CONFIG_MODVERSIONS is not set
# CONFIG_KMOD is not set
#
# General setup
#
CONFIG_NET=y
CONFIG_PCI=y
CONFIG_PCI_BIOS=y
CONFIG_PCI_DIRECT=y
CONFIG_PCI_QUIRKS=y
CONFIG_PCI_OLD_PROC=y
# CONFIG_MCA is not set
CONFIG_SYSVIPC=y
# CONFIG_BSD_PROCESS_ACCT is not set
CONFIG_SYSCTL=y
CONFIG_BINFMT_AOUT=y
CONFIG_BINFMT_ELF=y
CONFIG_BINFMT_MISC=y
CONFIG_PARPORT=y
CONFIG_PARPORT_PC=y
# CONFIG_PARPORT_OTHER is not set
# CONFIG_APM is not set
#
# Plug and Play support
#
CONFIG_PNP=y
# CONFIG_PNP_PARPORT is not set
#
# Block devices
#
CONFIG_BLK_DEV_FD=y
CONFIG_BLK_DEV_IDE=y
#
# Please see Documentation/ide.txt for help/info on IDE drives
#
# CONFIG_BLK_DEV_HD_IDE is not set
CONFIG_BLK_DEV_IDEDISK=y
CONFIG_BLK_DEV_IDECD=y
# CONFIG_BLK_DEV_IDETAPE is not set
# CONFIG_BLK_DEV_IDEFLOPPY is not set
# CONFIG_BLK_DEV_IDESCSI is not set
CONFIG_BLK_DEV_CMD640=y
# CONFIG_BLK_DEV_CMD640_ENHANCED is not set
CONFIG_BLK_DEV_RZ1000=y
CONFIG_BLK_DEV_IDEPCI=y
CONFIG_BLK_DEV_IDEDMA=y
# CONFIG_BLK_DEV_OFFBOARD is not set
CONFIG_IDEDMA_AUTO=y
# CONFIG_IDE_CHIPSETS is not set
#
# Additional Block Devices
#
# CONFIG_BLK_DEV_LOOP is not set
# CONFIG_BLK_DEV_NBD is not set
# CONFIG_BLK_DEV_MD is not set
# CONFIG_BLK_DEV_RAM is not set
# CONFIG_BLK_DEV_XD is not set
CONFIG_PARIDE_PARPORT=y
# CONFIG_PARIDE is not set
# CONFIG_BLK_DEV_HD is not set
#
# Networking options
#
CONFIG_PACKET=y
CONFIG_NETLINK=y
CONFIG_RTNETLINK=y
# CONFIG_NETLINK_DEV is not set
CONFIG_FIREWALL=y
CONFIG_NET_ALIAS=y
CONFIG_FILTER=y
CONFIG_UNIX=y
CONFIG_INET=y
# CONFIG_IP_MULTICAST is not set
# CONFIG_IP_ADVANCED_ROUTER is not set
# CONFIG_IP_PNP is not set
CONFIG_IP_FIREWALL=y
# CONFIG_IP_FIREWALL_NETLINK is not set
CONFIG_IP_TRANSPARENT_PROXY=y
CONFIG_IP_ALWAYS_DEFRAG=y
CONFIG_IP_MASQUERADE=y
#
# Protocol-specific masquerading support will be built as modules.
#
CONFIG_IP_MASQUERADE_ICMP=y
#
# Protocol-specific masquerading support will be built as modules.
#
# CONFIG_IP_ROUTER is not set
CONFIG_NET_IPIP=y
CONFIG_NET_IPGRE=y
CONFIG_IP_ALIAS=y
CONFIG_SYN_COOKIES=y
#
# (it is safe to leave these untouched)
#
CONFIG_INET_RARP=y
CONFIG_IP_NOSR=y
CONFIG_SKB_LARGE=y
#
#
#
# CONFIG_IPX is not set
# CONFIG_ATALK is not set
#
# SCSI support
#
CONFIG_SCSI=y
#
# SCSI support type (disk, tape, CD-ROM)
#
CONFIG_BLK_DEV_SD=y
CONFIG_CHR_DEV_ST=y
CONFIG_BLK_DEV_SR=y
# CONFIG_BLK_DEV_SR_VENDOR is not set
CONFIG_CHR_DEV_SG=y
#
# Some SCSI devices (e.g. CD jukebox) support multiple LUNs
#
CONFIG_SCSI_MULTI_LUN=y
# CONFIG_SCSI_CONSTANTS is not set
# CONFIG_SCSI_LOGGING is not set
#
# SCSI low-level drivers
#
# CONFIG_SCSI_7000FASST is not set
# CONFIG_SCSI_AHA152X is not set
# CONFIG_SCSI_AHA1542 is not set
# CONFIG_SCSI_AHA1740 is not set
CONFIG_SCSI_AIC7XXX=y
# CONFIG_OVERRIDE_CMDS is not set
# CONFIG_AIC7XXX_PROC_STATS is not set
CONFIG_AIC7XXX_RESET_DELAY=8
# CONFIG_SCSI_ADVANSYS is not set
# CONFIG_SCSI_IN2000 is not set
# CONFIG_SCSI_AM53C974 is not set
# CONFIG_SCSI_BUSLOGIC is not set
# CONFIG_SCSI_DTC3280 is not set
# CONFIG_SCSI_EATA_DMA is not set
# CONFIG_SCSI_EATA_PIO is not set
# CONFIG_SCSI_EATA is not set
# CONFIG_SCSI_FUTURE_DOMAIN is not set
# CONFIG_SCSI_GDTH is not set
# CONFIG_SCSI_GENERIC_NCR5380 is not set
# CONFIG_SCSI_PPA is not set
# CONFIG_SCSI_IMM is not set
# CONFIG_SCSI_G_NCR5380_PORT is not set
# CONFIG_SCSI_G_NCR5380_MEM is not set
# CONFIG_SCSI_NCR53C406A is not set
# CONFIG_SCSI_NCR53C7xx is not set
# CONFIG_SCSI_NCR53C8XX is not set
# CONFIG_SCSI_PAS16 is not set
# CONFIG_SCSI_PCI2000 is not set
# CONFIG_SCSI_PCI2220I is not set
# CONFIG_SCSI_PSI240I is not set
# CONFIG_SCSI_QLOGIC_FAS is not set
# CONFIG_SCSI_QLOGIC_ISP is not set
# CONFIG_SCSI_SEAGATE is not set
# CONFIG_SCSI_DC390T is not set
# CONFIG_SCSI_T128 is not set
# CONFIG_SCSI_U14_34F is not set
# CONFIG_SCSI_ULTRASTOR is not set
#
# Network device support
#
CONFIG_NETDEVICES=y
# CONFIG_ARCNET is not set
# CONFIG_DUMMY is not set
# CONFIG_EQUALIZER is not set
CONFIG_NET_ETHERNET=y
CONFIG_NET_VENDOR_3COM=y
# CONFIG_EL1 is not set
# CONFIG_EL2 is not set
# CONFIG_ELPLUS is not set
# CONFIG_EL3 is not set
# CONFIG_3C515 is not set
CONFIG_VORTEX=y
# CONFIG_LANCE is not set
# CONFIG_NET_VENDOR_SMC is not set
# CONFIG_NET_VENDOR_RACAL is not set
CONFIG_NET_ISA=y
# CONFIG_E2100 is not set
# CONFIG_DEPCA is not set
# CONFIG_EWRK3 is not set
# CONFIG_EEXPRESS is not set
# CONFIG_HPLAN_PLUS is not set
# CONFIG_HPLAN is not set
# CONFIG_HP100 is not set
CONFIG_NE2000=y
# CONFIG_SK_G16 is not set
CONFIG_NET_EISA=y
# CONFIG_PCNET32 is not set
# CONFIG_APRICOT is not set
# CONFIG_CS89x0 is not set
# CONFIG_DE4X5 is not set
# CONFIG_DEC_ELCP is not set
# CONFIG_DGRS is not set
# CONFIG_EEXPRESS_PRO100 is not set
CONFIG_NE2K_PCI=y
# CONFIG_TLAN is not set
# CONFIG_VIA_RHINE is not set
# CONFIG_NET_POCKET is not set
# CONFIG_FDDI is not set
# CONFIG_DLCI is not set
# CONFIG_PLIP is not set
CONFIG_PPP=y
#
# CCP compressors for PPP are only built as modules.
#
# CONFIG_SLIP is not set
# CONFIG_NET_RADIO is not set
# CONFIG_TR is not set
# CONFIG_WAN_DRIVERS is not set
#
# Amateur Radio support
#
# CONFIG_HAMRADIO is not set
#
# ISDN subsystem
#
# CONFIG_ISDN is not set
#
# CD-ROM drivers (not for SCSI or IDE/ATAPI drives)
#
# CONFIG_CD_NO_IDESCSI is not set
#
# Character devices
#
CONFIG_VT=y
CONFIG_VT_CONSOLE=y
CONFIG_SERIAL=y
CONFIG_SERIAL_CONSOLE=y
CONFIG_SERIAL_EXTENDED=y
# CONFIG_SERIAL_MANY_PORTS is not set
CONFIG_SERIAL_SHARE_IRQ=y
CONFIG_SERIAL_DETECT_IRQ=y
# CONFIG_SERIAL_MULTIPORT is not set
# CONFIG_HUB6 is not set
# CONFIG_SERIAL_NONSTANDARD is not set
CONFIG_UNIX98_PTYS=y
CONFIG_UNIX98_PTY_COUNT=2048
CONFIG_PRINTER=y
CONFIG_PRINTER_READBACK=y
CONFIG_MOUSE=y
# CONFIG_ATIXL_BUSMOUSE is not set
# CONFIG_BUSMOUSE is not set
# CONFIG_MS_BUSMOUSE is not set
CONFIG_PSMOUSE=y
# CONFIG_82C710_MOUSE is not set
# CONFIG_PC110_PAD is not set
# CONFIG_QIC02_TAPE is not set
CONFIG_WATCHDOG=y
# CONFIG_WATCHDOG_NOWAYOUT is not set
# CONFIG_WDT is not set
CONFIG_SOFT_WATCHDOG=y
# CONFIG_PCWATCHDOG is not set
# CONFIG_ACQUIRE_WDT is not set
# CONFIG_RTC is not set
# CONFIG_VIDEO_DEV is not set
# CONFIG_NVRAM is not set
# CONFIG_JOYSTICK is not set
#
# Ftape, the floppy tape device driver
#
# CONFIG_FTAPE is not set
# CONFIG_FT_NORMAL_DEBUG is not set
# CONFIG_FT_FULL_DEBUG is not set
# CONFIG_FT_NO_TRACE is not set
# CONFIG_FT_NO_TRACE_AT_ALL is not set
# CONFIG_FT_STD_FDC is not set
# CONFIG_FT_MACH2 is not set
# CONFIG_FT_PROBE_FC10 is not set
# CONFIG_FT_ALT_FDC is not set
#
# Filesystems
#
# CONFIG_QUOTA is not set
# CONFIG_MINIX_FS is not set
CONFIG_EXT2_FS=y
CONFIG_ISO9660_FS=y
CONFIG_JOLIET=y
CONFIG_FAT_FS=y
CONFIG_MSDOS_FS=y
# CONFIG_UMSDOS_FS is not set
# CONFIG_VFAT_FS is not set
CONFIG_PROC_FS=y
CONFIG_NFS_FS=y
# CONFIG_NFSD is not set
CONFIG_SUNRPC=y
CONFIG_LOCKD=y
# CONFIG_CODA_FS is not set
# CONFIG_SMB_FS is not set
# CONFIG_NCP_FS is not set
# CONFIG_HPFS_FS is not set
# CONFIG_NTFS_FS is not set
# CONFIG_SYSV_FS is not set
# CONFIG_AFFS_FS is not set
# CONFIG_HFS_FS is not set
# CONFIG_ROMFS_FS is not set
# CONFIG_AUTOFS_FS is not set
# CONFIG_UFS_FS is not set
# CONFIG_BSD_DISKLABEL is not set
# CONFIG_SMD_DISKLABEL is not set
# CONFIG_SOLARIS_X86_PARTITION is not set
CONFIG_DEVPTS_FS=y
# CONFIG_MAC_PARTITION is not set
CONFIG_NLS=y
#
# Native Language Support
#
# CONFIG_NLS_CODEPAGE_437 is not set
# CONFIG_NLS_CODEPAGE_737 is not set
# CONFIG_NLS_CODEPAGE_775 is not set
# CONFIG_NLS_CODEPAGE_850 is not set
# CONFIG_NLS_CODEPAGE_852 is not set
# CONFIG_NLS_CODEPAGE_855 is not set
# CONFIG_NLS_CODEPAGE_857 is not set
# CONFIG_NLS_CODEPAGE_860 is not set
# CONFIG_NLS_CODEPAGE_861 is not set
# CONFIG_NLS_CODEPAGE_862 is not set
# CONFIG_NLS_CODEPAGE_863 is not set
# CONFIG_NLS_CODEPAGE_864 is not set
# CONFIG_NLS_CODEPAGE_865 is not set
# CONFIG_NLS_CODEPAGE_866 is not set
# CONFIG_NLS_CODEPAGE_869 is not set
# CONFIG_NLS_CODEPAGE_874 is not set
# CONFIG_NLS_ISO8859_1 is not set
# CONFIG_NLS_ISO8859_2 is not set
# CONFIG_NLS_ISO8859_3 is not set
# CONFIG_NLS_ISO8859_4 is not set
# CONFIG_NLS_ISO8859_5 is not set
# CONFIG_NLS_ISO8859_6 is not set
# CONFIG_NLS_ISO8859_7 is not set
# CONFIG_NLS_ISO8859_8 is not set
# CONFIG_NLS_ISO8859_9 is not set
# CONFIG_NLS_KOI8_R is not set
#
# Console drivers
#
CONFIG_VGA_CONSOLE=y
CONFIG_VIDEO_SELECT=y
#
# Sound
#
CONFIG_SOUND=y
# CONFIG_SOUND_MSNDCLAS is not set
# CONFIG_SOUND_MSNDPIN is not set
CONFIG_SOUND_OSS=y
# CONFIG_SOUND_PAS is not set
CONFIG_SOUND_SB=y
CONFIG_SB_BASE=220
CONFIG_SB_IRQ=10
CONFIG_SB_DMA=1
CONFIG_SB_DMA2=5
CONFIG_SB_MPU_BASE=330
#
# MPU401 IRQ is only required with Jazz16, SM Wave and ESS1688.
#
#
# Enter -1 to the following question if you have something else such as SB16/32.
#
CONFIG_SB_MPU_IRQ=-1
# CONFIG_SOUND_ADLIB is not set
# CONFIG_SOUND_GUS is not set
# CONFIG_SOUND_MPU401 is not set
# CONFIG_SOUND_PSS is not set
# CONFIG_SOUND_MSS is not set
# CONFIG_SOUND_SSCAPE is not set
# CONFIG_SOUND_TRIX is not set
# CONFIG_SOUND_MAD16 is not set
# CONFIG_SOUND_WAVEFRONT is not set
# CONFIG_SOUND_CS4232 is not set
# CONFIG_SOUND_OPL3SA2 is not set
# CONFIG_SOUND_MAUI is not set
# CONFIG_SOUND_SGALAXY is not set
# CONFIG_SOUND_OPL3SA1 is not set
# CONFIG_SOUND_SOFTOSS is not set
# CONFIG_SOUND_YM3812 is not set
# CONFIG_SOUND_VMIDI is not set
# CONFIG_SOUND_UART6850 is not set
#
# Additional low level sound drivers
#
# CONFIG_LOWLEVEL_SOUND is not set
#
# Kernel hacking
#
CONFIG_MAGIC_SYSRQ=y
-
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