When gigaset_initbcs() is called, cs->dev is not initialized yet. If
dev_alloc_skb() failed in this function, NULL poinster dereference will
happen at dev_warn().
Cc: Kai Germaschewski <kai.germaschewski@gmx.de>
Cc: Hansjoerg Lipp <hjlipp@web.de>
Cc: Tilman Schmidt <tilman@imap.cc>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ioremap must be balanced by an iounmap and failing to do so can result
in a memory leak.
Signed-off-by: Amol Lad <amol@verismonetworks.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Most of the ISDN ->readstat() implementations needed to check
copy_to_user() and put_user() return values.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a particularly ugly on-failure bug, possibly security, since the
lack of error handling here is covering up another class of bug: failure to
handle copy_to_user() return values.
The I4L API function ->readstat() returns an integer, and by looking at
several existing driver implementations, it is clear that a negative return
value was meant to indicate an error.
Given that several drivers already return a negative value indicating an
errno-style error, the current code would blindly accept that [negative]
value as a valid amount of bytes read. Obvious damage ensues.
Correcting ->readstat() handling to properly notice errors fixes the
existing code to work correctly on error, and enables future patches to
more easily indicate errors during operation.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Cc: Karsten Keil <kkeil@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With Karsten Keil <kkeil@suse.de>
save_flags()/cli() pair is replaced with spin_lock_irqsave() and
restore_flags() replaced with spin_unlock_irqrestore()
Tested compile only using allmodconfig
Signed-off-by: Amol Lad <amol@verismonetworks.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
pcbit: kill 'may be used uninitialized' warning. although the code does
eventually fill the 32 bits it cares about, the variable truly is
accessed uninitialized in each macro. Easier to just clean it up now.
sc: fix a ton of obviously incorrect printk's (some with missing
arguments even)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Eliminate irq->card lookup table, by properly passing the card pointer
via request_irq() like other drivers.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Many files include the filename at the beginning, serveral used a wrong one.
Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
drivers/isdn/sc/event.c: In function 'indicate_status':
drivers/isdn/sc/event.c:49: error: 'events' undeclared (first use in this function)
drivers/isdn/sc/event.c:49: error: (Each undeclared identifier is reported only once
drivers/isdn/sc/event.c:49: error: for each function it appears in.)
drivers/isdn/sc/event.c:49: warning: format '%d' expects type 'int', but argument 4 has type 'ulong'
drivers/isdn/sc/interrupt.c: In function 'interrupt_handler':
drivers/isdn/sc/interrupt.c:97: warning: format '%x' expects type 'unsigned int', but argument 4 has type 'long unsigned int'
drivers/isdn/sc/timer.c: In function 'check_reset':
drivers/isdn/sc/timer.c:80: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
Acked-by: Karsten Keil <kkeil@suse.de>
Cc: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When pr_debug() is enabled:
drivers/isdn/sc/command.c: In function 'command':
drivers/isdn/sc/command.c:107: error: 'commands' undeclared (first use in this function)
drivers/isdn/sc/command.c:107: error: (Each undeclared identifier is reported only once
drivers/isdn/sc/command.c:107: error: for each function it appears in.)
drivers/isdn/sc/command.c:122: warning: format '%x' expects type 'unsigned int', but argument 3 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'dial':
drivers/isdn/sc/command.c:199: warning: format '%d' expects type 'int', but argument 4 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'answer':
drivers/isdn/sc/command.c:221: warning: format '%s' expects type 'char *', but argument 3 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'hangup':
drivers/isdn/sc/command.c:244: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'setl2':
drivers/isdn/sc/command.c:265: error: 'l2protos' undeclared (first use in this function)
drivers/isdn/sc/command.c: In function 'setl3':
drivers/isdn/sc/command.c:297: error: 'l3protos' undeclared (first use in this function)
drivers/isdn/sc/command.c:297: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'acceptb':
drivers/isdn/sc/command.c:315: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'clreaz':
drivers/isdn/sc/command.c:330: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
drivers/isdn/sc/command.c: In function 'seteaz':
drivers/isdn/sc/command.c:345: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
Cc: Zach Brown <zach.brown@oracle.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clean up warnings in drivers/isdn by using long not int for the values
where we pass void * and cast to integer types. The code is ok (ok passing
the stuff this way isn't pretty but the code is valid). In all the cases I
checked out the right thing happens anyway but this removes all the
warnings.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As reported in http://bugzilla.kernel.org/show_bug.cgi?id=6970, ISDN can issue
excessively-long udelays, which triggers a build-time error on ARM.
This is very sucky of ISDN, but I doubt if anyone is going to suddenly fix it.
So change the macro to do the microsecond counting itself.
Cc: <tch@wpkg.org>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch to the Siemens Gigaset driver fixes the compile warning
"ignoring return value of 'class_device_create_file', declared with
attribute warn_unused_result" appearing with CONFIG_ENABLE_MUST_CHECK=y in
release 2.6.18-rc1-mm1.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Acked-by: Hansjoerg Lipp <hjlipp@web.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking. One of these
structures was a struct tty_operations. In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.
This patch declares all struct tty_operations in the tree as const. In all
cases, they are static and used only as input to tty_set_operations. As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.
53 drivers are affected. I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months. serial_core.c was the busiest one that I looked at.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ifa_local, ifa_address, ifa_mask, ifa_broadcast and ifa_anycast are
net-endian. Annotated them and variables that are inferred to be
net-endian.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The purpose of this patch is to split off the case when a device does
not reply on the lower level (which is reported by HC hardware), and
a case when the device accepted the request, but does not reply at
upper level. This redefinition allows to diagnose issues easier,
without asking the user if the -110 happened "immediately".
The usbmon splits such cases already thanks to its timestamp, but
it's not always available.
I adjusted all drivers which I found affected (by searching for "urb").
Out of tree drivers may suffer a little bit, but I do not expect much
breakage. At worst they may print a few messages.
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This eliminates the i_blksize field from struct inode. Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.
Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.
[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* MODE_MASK is unused in eicon driver.
* Conflicts with a ptrace stuff on arm.
drivers/isdn/hardware/eicon/divasync.h:259:1: warning: "MODE_MASK" redefined
include2/asm/ptrace.h:48:1: warning: this is the location of the previous definition
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Acked-by: Armin Schindler <armin@melware.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert selection of serial line header compression to use CONFIG_SLHC
rather than makefile ifeq uglyness. This makes it easier to select
the SLHC module from other code.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix the warnings about the section mismatches for __init* in the HiSax
driver.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6: (22 commits)
[PATCH] devfs: Remove it from the feature_removal.txt file
[PATCH] devfs: Last little devfs cleanups throughout the kernel tree.
[PATCH] devfs: Rename TTY_DRIVER_NO_DEVFS to TTY_DRIVER_DYNAMIC_DEV
[PATCH] devfs: Remove the tty_driver devfs_name field as it's no longer needed
[PATCH] devfs: Remove the line_driver devfs_name field as it's no longer needed
[PATCH] devfs: Remove the videodevice devfs_name field as it's no longer needed
[PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
[PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed
[PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
[PATCH] devfs: Remove devfs_remove() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_bdev() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_symlink() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
[PATCH] devfs: Remove devfs_*_tape() functions from the kernel tree
[PATCH] devfs: Remove devfs support from the sound subsystem
[PATCH] devfs: Remove devfs support from the ide subsystem.
[PATCH] devfs: Remove devfs support from the serial subsystem
[PATCH] devfs: Remove devfs from the init code
[PATCH] devfs: Remove devfs from the partition code
...
If all drivers go away before all ISDN network interfaces are closed we got
a OOps on removing interfaces, this patch avoid it.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
most current laptops do not work without allowing shared cardbus IRQs.
This patch enables IRQ sharing, so these cards work again.
This was tested with shared and none shared cardbus IRQs on different laptops
without problems.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6:
[PATCH] i386: export memory more than 4G through /proc/iomem
[PATCH] 64bit Resource: finally enable 64bit resource sizes
[PATCH] 64bit Resource: convert a few remaining drivers to use resource_size_t where needed
[PATCH] 64bit resource: change pnp core to use resource_size_t
[PATCH] 64bit resource: change pci core and arch code to use resource_size_t
[PATCH] 64bit resource: change resource core to use resource_size_t
[PATCH] 64bit resource: introduce resource_size_t for the start and end of struct resource
[PATCH] 64bit resource: fix up printks for resources in misc drivers
[PATCH] 64bit resource: fix up printks for resources in arch and core code
[PATCH] 64bit resource: fix up printks for resources in pcmcia drivers
[PATCH] 64bit resource: fix up printks for resources in video drivers
[PATCH] 64bit resource: fix up printks for resources in ide drivers
[PATCH] 64bit resource: fix up printks for resources in mtd drivers
[PATCH] 64bit resource: fix up printks for resources in pci core and hotplug drivers
[PATCH] 64bit resource: fix up printks for resources in networks drivers
[PATCH] 64bit resource: fix up printks for resources in sound drivers
[PATCH] 64bit resource: C99 changes for struct resource declarations
Fixed up trivial conflict in drivers/ide/pci/cmd64x.c (the printk that
was changed by the 64-bit resources had been deleted in the meantime ;)
Coverity spotted this leak (id #613), when we are not configured, we return
without freeing the allocated skb.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
DLE masking was non-functional since the new tty handling.
Found by Peter Evertz <leo2@pec.homeip.net>
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
locking init cleanups:
- convert " = SPIN_LOCK_UNLOCKED" to spin_lock_init() or DEFINE_SPINLOCK()
- convert rwlocks in a similar manner
this patch was generated automatically.
Motivation:
- cleanliness
- lockdep needs control of lock initialization, which the open-coded
variants do not give
- it's also useful for -rt and for lock debugging in general
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Based on a patch series originally from Vivek Goyal <vgoyal@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is needed if we wish to change the size of the resource structures.
Based on an original patch from Vivek Goyal <vgoyal@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
typo fixes
Clean up 'inline is not at beginning' warnings for usb storage
Storage class should be first
i386: Trivial typo fixes
ixj: make ixj_set_tone_off() static
spelling fixes
fix paniced->panicked typos
Spelling fixes for Documentation/atomic_ops.txt
move acknowledgment for Mark Adler to CREDITS
remove the bouncing email address of David Campbell
The changes in the tty handling contain a bug while accessing
the last byte in the skb. Since special sequence for control of
DTMF and FAX via ttyI* devices handled via this path, these services
do not work anymore.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've always found this flag confusing. Now that devfs is no longer around, it
has been renamed, and the documentation for when this flag should be used has
been updated.
Also fixes all drivers that use this flag.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The following patch to the common part of the Siemens Gigaset driver
prevents it from trying to send the +++ break sequence if the device has
been disconnected, and removes a couple of assignments which didn't have
any effect.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Acked-by: Hansjoerg Lipp <hjlipp@web.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch to the Siemens Gigaset base driver adds graceful
recovery for some frequently encountered error conditions, by retrying
failed control requests (eg. stalled control pipe), and by closing and
reopening the AT command channel when it appears to be stuck.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Acked-by: Hansjoerg Lipp <hjlipp@web.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes coverity bug #517.
Since IESIZE is greater than IESIZE_NI1 we might run past the end of
ielist_ni1. This fixes it by using the proper IESIZE_NI1 define.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I am getting more or less reproducible crashes from the CAPI subsystem
using the fcdsl driver:
Unable to handle kernel NULL pointer dereference at virtual address 00000010
printing eip:
c39bbca4
*pde = 00000000
Oops: 0000 [#1]
Modules linked in: netconsole capi capifs 3c59x mii fcdsl kernelcapi uhci_hcd usbcore ide_cd cdrom
CPU: 0
EIP: 0060:[<c39bbca4>] Tainted: P VLI
EFLAGS: 00010202 (2.6.16.11 #3)
EIP is at handle_minor_send+0x17a/0x241 [capi]
eax: c24abbc0 ebx: c0b4c980 ecx: 00000010 edx: 00000010
esi: c1679140 edi: c2783016 ebp: 0000c28d esp: c0327e24
ds: 007b es: 007b ss: 0068
Process swapper (pid: 0, threadinfo=c0326000 task=c02e1300)
Stack: <0>000005b4 c1679180 00000000 c28d0000 c1ce04e0 c2f69654 c221604e c1679140
c39bc19a 00000038 c20c0400 c075c560 c1f2f800 00000000 c01dc9b5 c1e96a40
c075c560 c2ed64c0 c1e96a40 c01dcd3b c2fb94e8 c075c560 c0327f00 c1e96a40
Call Trace:
[<c39bc19a>] capinc_tty_write+0xda/0xf3 [capi]
[<c01dc9b5>] ppp_sync_push+0x52/0xfe
[<c01dcd3b>] ppp_sync_send+0x1f5/0x204
[<c01d9bc1>] ppp_push+0x3e/0x9c
[<c01dacd4>] ppp_xmit_process+0x422/0x4cc
[<c01daf3f>] ppp_start_xmit+0x1c1/0x1f6
[<c0213ea5>] qdisc_restart+0xa7/0x135
[<c020b112>] dev_queue_xmit+0xba/0x19e
[<c0223f69>] ip_output+0x1eb/0x236
[<c0220907>] ip_forward+0x1c1/0x21a
[<c021fa6c>] ip_rcv+0x38e/0x3ea
[<c020b4c2>] netif_receive_skb+0x166/0x195
[<c020b55e>] process_backlog+0x6d/0xd2
[<c020a30f>] net_rx_action+0x6a/0xff
[<c0112909>] __do_softirq+0x35/0x7d
[<c0112973>] do_softirq+0x22/0x26
[<c0103a9d>] do_IRQ+0x1e/0x25
[<c010255a>] common_interrupt+0x1a/0x20
[<c01013c5>] default_idle+0x2b/0x53
[<c0101426>] cpu_idle+0x39/0x4e
[<c0328386>] start_kernel+0x20b/0x20d
Code: c0 e8 b3 b6 77 fc 85 c0 75 10 68 d8 c8 9b c3 e8 82 3d 75 fc 8b 43 60 5a eb 50 8d 56 50 c7 00 00 00 00 00 66 89 68 04 eb 02 89
ca <8b> 0a 85 c9 75 f8 89 02 89 da ff 46 54 8b 46 10 e8 30 79 fd ff
<0>Kernel panic - not syncing: Fatal exception in interrupt
That oops took me to the "ackqueue" implementation in capi.c. The crash
occured in capincci_add_ack() (auto-inlined by the compiler).
I read the code a bit and finally decided to replace the custom linked list
implementation (struct capiminor->ackqueue) by a struct list_head. That
did not solve the crash, but produced the following interresting oops:
Unable to handle kernel paging request at virtual address 00200200
printing eip:
c39bb1f5
*pde = 00000000
Oops: 0002 [#1]
Modules linked in: netconsole capi capifs 3c59x mii fcdsl kernelcapi uhci_hcd usbcore ide_cd cdrom
CPU: 0
EIP: 0060:[<c39bb1f5>] Tainted: P VLI
EFLAGS: 00010246 (2.6.16.11 #3)
EIP is at capiminor_del_ack+0x18/0x49 [capi]
eax: 00200200 ebx: c18d41a0 ecx: c1385620 edx: 00100100
esi: 0000d147 edi: 00001103 ebp: 0000d147 esp: c1093f3c
ds: 007b es: 007b ss: 0068
Process events/0 (pid: 3, threadinfo=c1092000 task=c1089030)
Stack: <0>c2a17580 c18d41a0 c39bbd16 00000038 c18d41e0 00000000 d147c640 c29e0b68
c29e0b90 00000212 c29e0b68 c39932b2 c29e0bb0 c10736a0 c0119ef0 c399326c
c10736a8 c10736a0 c10736b0 c0119f93 c011a06e 00000001 00000000 00000000
Call Trace:
[<c39bbd16>] handle_minor_send+0x1af/0x241 [capi]
[<c39932b2>] recv_handler+0x46/0x5f [kernelcapi]
[<c0119ef0>] run_workqueue+0x5e/0x8d
[<c399326c>] recv_handler+0x0/0x5f [kernelcapi]
[<c0119f93>] worker_thread+0x0/0x10b
[<c011a06e>] worker_thread+0xdb/0x10b
[<c010c998>] default_wake_function+0x0/0xc
[<c011c399>] kthread+0x90/0xbc
[<c011c309>] kthread+0x0/0xbc
[<c0100a65>] kernel_thread_helper+0x5/0xb
Code: 7e 02 89 ee 89 f0 5a f7 d0 c1 f8 1f 5b 21 f0 5e 5f 5d c3 56 53 8b 48 50 89 d6 89 c3 8b 11 eb 2f 66 39 71 08 75 25 8b 41 04 8b 11 <89> 10 89 42 04 c7 01 00 01 10 00 89 c8 c7 41 04 00 02 20 00 e8
The interresting part of it is the "virtual address 00200200", which is
LIST_POISON2. I thought about some race condition, but as this is an UP
system, it leads to questions on how it can happen. If we look at EFLAGS:
00010202, we see that interrupts are enabled at the time of the crash
(eflags & 0x200).
Finally, I don't understand all the capi code, but I think that
handle_minor_send() is racing somehow against capi_recv_message(), which
call both capiminor_del_ack(). So if an IRQ occurs in the middle of
capiminor_del_ack() and another instance of it is invoked, it leads to
linked list corruption.
I came up with the following patch. With this, I could not reproduce the
crash anymore. Clearly, this is not the correct fix for the issue. As this
seems to be some locking issue, there might be more locking issues in that
code. For example, doesn't the whole struct capiminor have to be locked
somehow?
Cc: Carsten Paeth <calle@calle.de>
Cc: Kai Germaschewski <kai.germaschewski@gmx.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
