Eric Lee / smarc-fsl-linux-kernel

07 Feb, 2008

1 commit

30 Jan, 2008

2 commits

  • 71c339116   debug: add the end-of-trace marker and the module list to ... Browse Code »

    Unlike oopses, WARN_ON() currently does't print the loaded modules list.
    This makes it harder to take action on certain bug reports. For example,
    recently there were a set of WARN_ON()s reported in the mac80211 stack,
    which were just signalling a driver bug. It takes then anther round trip
    to the bug reporter (if he responds at all) to find out which driver
    is at fault.

    Another issue is that, unlike oopses, WARN_ON() doesn't currently printk
    the helpful "cut here" line, nor the "end of trace" marker.
    Now that WARN_ON() is out of line, the size increase due to this is
    minimal and it's worth adding.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Ingo Molnar
    Signed-off-by: Thomas Gleixner

    Arjan van de Ven
     
  • 79b4cc5ee   debug: move WARN_ON() out of line ... Browse Code »

    A quick grep shows that there are currently 1145 instances of WARN_ON
    in the kernel. Currently, WARN_ON is pretty much entirely inlined,
    which makes it hard to enhance it without growing the size of the kernel
    (and getting Andrew unhappy).

    This patch build on top of Olof's patch that introduces __WARN,
    and places the slowpath out of line. It also uses Ingo's suggestion
    to not use __FUNCTION__ but to use kallsyms to do the lookup;
    this saves a ton of extra space since gcc doesn't need to store the function
    string twice now:

    3936367 833603 624736 5394706 525112 vmlinux.before
    3917508 833603 624736 5375847 520767 vmlinux-slowpath

    15Kb savings...

    Signed-off-by: Arjan van de Ven
    CC: Andrew Morton
    CC: Olof Johansson
    Acked-by: Matt Meckall
    Signed-off-by: Ingo Molnar
    Signed-off-by: Thomas Gleixner

    Arjan van de Ven
     

20 Dec, 2007

1 commit

  • 2c3b20e91   debug: add end-of-oops marker ... Browse Code »

    Right now it's nearly impossible for parsers that collect kernel crashes
    from logs or emails (such as www.kerneloops.org) to detect the
    end-of-oops condition. In addition, it's not currently possible to
    detect whether or not 2 oopses that look alike are actually the same
    oops reported twice, or are truly two unique oopses.

    This patch adds an end-of-oops marker, and makes the end marker include
    a very simple 64-bit random ID to be able to detect duplicate reports.

    Normally, this ID is calculated as a late_initcall() (in the hope that
    at that time there is enough entropy to get a unique enough ID); however
    for early oopses the oops_exit() function needs to generate the ID on
    the fly.

    We do this all at the _end_ of an oops printout, so this does not impact
    our ability to get the most important portions of a crash out to the
    console first.

    [ Sidenote: the already existing oopses-since-bootup counter we print
    during crashes serves as the differentiator between multiple oopses
    that trigger during the same bootup. ]

    Tested on 32-bit and 64-bit x86. Artificially injected very early
    crashes as well, as expected they result in this constant ID after
    multiple bootups:

    ---[ end trace ca143223eefdc828 ]---
    ---[ end trace ca143223eefdc828 ]---

    because the random pools are still all zero. But it all still works
    fine and causes no additional problems (which is the main goal of
    instrumentation code).

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Ingo Molnar

    Arjan van de Ven
     

20 Oct, 2007

1 commit

19 Oct, 2007

1 commit

18 Jul, 2007

1 commit

  • bcdcd8e72   Report that kernel is tainted if there was an OOPS ... Browse Code »

    If the kernel OOPSed or BUGed then it probably should be considered as
    tainted. Thus, all subsequent OOPSes and SysRq dumps will report the
    tainted kernel. This saves a lot of time explaining oddities in the
    calltraces.

    Signed-off-by: Pavel Emelianov
    Acked-by: Randy Dunlap
    Cc:
    Signed-off-by: Andrew Morton
    [ Added parisc patch from Matthew Wilson -Linus ]
    Signed-off-by: Linus Torvalds

    Pavel Emelianov
     

12 Feb, 2007

1 commit

  • 34f5a3989   [PATCH] Add TAINT_USER and ability to set taint flags from userspace ... Browse Code »

    Allow taint flags to be set from userspace by writing to
    /proc/sys/kernel/tainted, and add a new taint flag, TAINT_USER, to be used
    when userspace has potentially done something dangerous that might
    compromise the kernel. This will allow support personnel to ask further
    questions about what may have caused the user taint flag to have been set.

    For example, they might examine the logs of the realtime JVM to see if the
    Java program has used the really silly, stupid, dangerous, and
    completely-non-portable direct access to physical memory feature which MUST
    be implemented according to the Real-Time Specification for Java (RTSJ).
    Sigh. What were those silly people at Sun thinking?

    [akpm@osdl.org: build fix]
    [bunk@stusta.de: cleanup]
    Signed-off-by: "Theodore Ts'o"
    Signed-off-by: Adrian Bunk
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Theodore Ts'o
     

30 Sep, 2006

1 commit

26 Sep, 2006

2 commits

  • 3162f751d   [PATCH] Add the __stack_chk_fail() function ... Browse Code »

    GCC emits a call to a __stack_chk_fail() function when the stack canary is
    not matching the expected value.

    Since this is a bad security issue; lets panic the kernel rather than limping
    along; the kernel really can't be trusted anymore when this happens.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Ingo Molnar
    Signed-off-by: Andi Kleen
    CC: Andi Kleen

    Arjan van de Ven
     
  • 8da5adda9   [PATCH] x86: Allow users to force a panic on NMI ... Browse Code »

    To quote Alan Cox:

    The default Linux behaviour on an NMI of either memory or unknown is to
    continue operation. For many environments such as scientific computing
    it is preferable that the box is taken out and the error dealt with than
    an uncorrected parity/ECC error get propogated.

    A small number of systems do generate NMI's for bizarre random reasons
    such as power management so the default is unchanged. In other respects
    the new proc/sys entry works like the existing panic controls already in
    that directory.

    This is separate to the edac support - EDAC allows supported chipsets to
    handle ECC errors well, this change allows unsupported cases to at least
    panic rather than cause problems further down the line.

    Signed-off-by: Don Zickus
    Signed-off-by: Andi Kleen

    Don Zickus
     

07 Sep, 2006

1 commit

15 Aug, 2006

1 commit

  • 657b3010d   [PATCH] panic.c build fix ... Browse Code »

    kernel/panic.c: In function 'add_taint':
    kernel/panic.c:176: warning: implicit declaration of function 'debug_locks_off'

    Cc: Andi Kleen
    Signed-off-by: Andrew Morton
    Signed-off-by: Greg Kroah-Hartman

    Andrew Morton
     

11 Jul, 2006

1 commit

  • 2c16e9c88   [PATCH] lockdep: disable lock debugging when kernel state becomes untrusted ... Browse Code »

    Disable lockdep debugging in two situations where the integrity of the
    kernel no longer is guaranteed: when oopsing and when hitting a
    tainting-condition. The goal is to not get weird lockdep traces that don't
    make sense or are otherwise undebuggable, to not waste time.

    Lockdep assumes that the previous state it knows about is valid to operate,
    which is why lockdep turns itself off after the first violation it reports,
    after that point it can no longer make that assumption.

    A kernel oops means that the integrity of the kernel compromised; in
    addition anything lockdep would report is of lesser importance than the
    oops.

    All the tainting conditions are of similar integrity-violating nature and
    also make debugging/diagnosing more difficult.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven
     

01 Jul, 2006

1 commit

11 Apr, 2006

1 commit

28 Mar, 2006

1 commit

  • e041c6834   [PATCH] Notifier chain update: API changes ... Browse Code »

    The kernel's implementation of notifier chains is unsafe. There is no
    protection against entries being added to or removed from a chain while the
    chain is in use. The issues were discussed in this thread:

    http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2

    We noticed that notifier chains in the kernel fall into two basic usage
    classes:

    "Blocking" chains are always called from a process context
    and the callout routines are allowed to sleep;

    "Atomic" chains can be called from an atomic context and
    the callout routines are not allowed to sleep.

    We decided to codify this distinction and make it part of the API. Therefore
    this set of patches introduces three new, parallel APIs: one for blocking
    notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
    really just the old API under a new name). New kinds of data structures are
    used for the heads of the chains, and new routines are defined for
    registration, unregistration, and calling a chain. The three APIs are
    explained in include/linux/notifier.h and their implementation is in
    kernel/sys.c.

    With atomic and blocking chains, the implementation guarantees that the chain
    links will not be corrupted and that chain callers will not get messed up by
    entries being added or removed. For raw chains the implementation provides no
    guarantees at all; users of this API must provide their own protections. (The
    idea was that situations may come up where the assumptions of the atomic and
    blocking APIs are not appropriate, so it should be possible for users to
    handle these things in their own way.)

    There are some limitations, which should not be too hard to live with. For
    atomic/blocking chains, registration and unregistration must always be done in
    a process context since the chain is protected by a mutex/rwsem. Also, a
    callout routine for a non-raw chain must not try to register or unregister
    entries on its own chain. (This did happen in a couple of places and the code
    had to be changed to avoid it.)

    Since atomic chains may be called from within an NMI handler, they cannot use
    spinlocks for synchronization. Instead we use RCU. The overhead falls almost
    entirely in the unregister routine, which is okay since unregistration is much
    less frequent that calling a chain.

    Here is the list of chains that we adjusted and their classifications. None
    of them use the raw API, so for the moment it is only a placeholder.

    ATOMIC CHAINS
    -------------
    arch/i386/kernel/traps.c: i386die_chain
    arch/ia64/kernel/traps.c: ia64die_chain
    arch/powerpc/kernel/traps.c: powerpc_die_chain
    arch/sparc64/kernel/traps.c: sparc64die_chain
    arch/x86_64/kernel/traps.c: die_chain
    drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list
    kernel/panic.c: panic_notifier_list
    kernel/profile.c: task_free_notifier
    net/bluetooth/hci_core.c: hci_notifier
    net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain
    net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain
    net/ipv6/addrconf.c: inet6addr_chain
    net/netfilter/nf_conntrack_core.c: nf_conntrack_chain
    net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain
    net/netlink/af_netlink.c: netlink_chain

    BLOCKING CHAINS
    ---------------
    arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain
    arch/s390/kernel/process.c: idle_chain
    arch/x86_64/kernel/process.c idle_notifier
    drivers/base/memory.c: memory_chain
    drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list
    drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list
    drivers/macintosh/adb.c: adb_client_list
    drivers/macintosh/via-pmu.c sleep_notifier_list
    drivers/macintosh/via-pmu68k.c sleep_notifier_list
    drivers/macintosh/windfarm_core.c wf_client_list
    drivers/usb/core/notify.c usb_notifier_list
    drivers/video/fbmem.c fb_notifier_list
    kernel/cpu.c cpu_chain
    kernel/module.c module_notify_list
    kernel/profile.c munmap_notifier
    kernel/profile.c task_exit_notifier
    kernel/sys.c reboot_notifier_list
    net/core/dev.c netdev_chain
    net/decnet/dn_dev.c: dnaddr_chain
    net/ipv4/devinet.c: inetaddr_chain

    It's possible that some of these classifications are wrong. If they are,
    please let us know or submit a patch to fix them. Note that any chain that
    gets called very frequently should be atomic, because the rwsem read-locking
    used for blocking chains is very likely to incur cache misses on SMP systems.
    (However, if the chain's callout routines may sleep then the chain cannot be
    atomic.)

    The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
    material written by Keith Owens and suggestions from Paul McKenney and Andrew
    Morton.

    [jes@sgi.com: restructure the notifier chain initialization macros]
    Signed-off-by: Alan Stern
    Signed-off-by: Chandra Seetharaman
    Signed-off-by: Jes Sorensen
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Stern
     

23 Mar, 2006

1 commit

  • dd287796d   [PATCH] pause_on_oops command line option ... Browse Code »

    Attempt to fix the problem wherein people's oops reports scroll off the screen
    due to repeated oopsing or to oopses on other CPUs.

    If this happens the user can reboot with the `pause_on_oops=' option.
    It will allow the first oopsing CPU to print an oops record just a single
    time. Second oopsing attempts, or oopses on other CPUs will cause those CPUs
    to enter a tight loop until the specified number of seconds have elapsed.

    The patch implements the infrastructure generically in the expectation that
    architectures other than x86 will find it useful.

    Cc: Dave Jones
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrew Morton
     

11 Feb, 2006

1 commit

07 Jan, 2006

1 commit

  • 347a8dc3b   [PATCH] s390: cleanup Kconfig ... Browse Code »

    Sanitize some s390 Kconfig options. We have ARCH_S390, ARCH_S390X,
    ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT. Replace these 6 options by
    S390, 64BIT and COMPAT.

    Signed-off-by: Martin Schwidefsky
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Martin Schwidefsky
     

27 Jul, 2005

1 commit

26 Jun, 2005

2 commits

  • 6e274d144   [PATCH] kdump: Use real pt_regs from exception ... Browse Code »

    Makes kexec_crashdump() take a pt_regs * as an argument. This allows to
    get exact register state at the point of the crash. If we come from direct
    panic assertion NULL will be passed and the current registers saved before
    crashdump.

    This hooks into two places:
    die(): check the conditions under which we will panic when calling
    do_exit and go there directly with the pt_regs that caused the fatal
    fault.

    die_nmi(): If we receive an NMI lockup while in the kernel use the
    pt_regs and go directly to crash_kexec(). We're probably nested up badly
    at this point so this might be the only chance to escape with proper
    information.

    Signed-off-by: Alexander Nyberg
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alexander Nyberg
     
  • dc009d924   [PATCH] kexec: add kexec syscalls ... Browse Code »

    This patch introduces the architecture independent implementation the
    sys_kexec_load, the compat_sys_kexec_load system calls.

    Kexec on panic support has been integrated into the core patch and is
    relatively clean.

    In addition the hopefully architecture independent option
    crashkernel=size@location has been docuemented. It's purpose is to reserve
    space for the panic kernel to live, and where no DMA transfer will ever be
    setup to access.

    Signed-off-by: Eric Biederman
    Signed-off-by: Alexander Nyberg
    Signed-off-by: Adrian Bunk
    Signed-off-by: Vivek Goyal
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Eric W. Biederman
     

25 Apr, 2005

1 commit

  • a271c241a   [SPARC]: Stop-A printk cleanup ... Browse Code »

    This patch is incredibly trivial, but it does resolve some of the user
    confusion as to what "L1-A" actually is.

    Clarify printk message to refer to Stop-A (L1-A).

    Gentoo has a virtually identical patch in their kernel sources.

    Signed-off-by: Tom 'spot' Callaway
    Signed-off-by: David S. Miller

    Tom 'spot' Callaway
     

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds