1. 25 11月, 2010 1 次提交
    • H
      [S390] nmi: fix clock comparator revalidation · e8129c64
      Heiko Carstens 提交于
      On each machine check all registers are revalidated. The save area for
      the clock comparator however only contains the upper most seven bytes
      of the former contents, if valid.
      Therefore the machine check handler uses a store clock instruction to
      get the current time and writes that to the clock comparator register
      which in turn will generate an immediate timer interrupt.
      However within the lowcore the expected time of the next timer
      interrupt is stored. If the interrupt happens before that time the
      handler won't be called. In turn the clock comparator won't be
      reprogrammed and therefore the interrupt condition stays pending which
      causes an interrupt loop until the expected time is reached.
      
      On NOHZ machines this can result in unresponsive machines since the
      time of the next expected interrupted can be a couple of days in the
      future.
      
      To fix this just revalidate the clock comparator register with the
      expected value.
      In addition the special handling for udelay must be changed as well.
      Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      e8129c64
  2. 18 11月, 2010 1 次提交
  3. 10 11月, 2010 2 次提交
  4. 29 10月, 2010 6 次提交
  5. 28 10月, 2010 1 次提交
  6. 25 10月, 2010 15 次提交
  7. 15 10月, 2010 1 次提交
    • A
      llseek: automatically add .llseek fop · 6038f373
      Arnd Bergmann 提交于
      All file_operations should get a .llseek operation so we can make
      nonseekable_open the default for future file operations without a
      .llseek pointer.
      
      The three cases that we can automatically detect are no_llseek, seq_lseek
      and default_llseek. For cases where we can we can automatically prove that
      the file offset is always ignored, we use noop_llseek, which maintains
      the current behavior of not returning an error from a seek.
      
      New drivers should normally not use noop_llseek but instead use no_llseek
      and call nonseekable_open at open time.  Existing drivers can be converted
      to do the same when the maintainer knows for certain that no user code
      relies on calling seek on the device file.
      
      The generated code is often incorrectly indented and right now contains
      comments that clarify for each added line why a specific variant was
      chosen. In the version that gets submitted upstream, the comments will
      be gone and I will manually fix the indentation, because there does not
      seem to be a way to do that using coccinelle.
      
      Some amount of new code is currently sitting in linux-next that should get
      the same modifications, which I will do at the end of the merge window.
      
      Many thanks to Julia Lawall for helping me learn to write a semantic
      patch that does all this.
      
      ===== begin semantic patch =====
      // This adds an llseek= method to all file operations,
      // as a preparation for making no_llseek the default.
      //
      // The rules are
      // - use no_llseek explicitly if we do nonseekable_open
      // - use seq_lseek for sequential files
      // - use default_llseek if we know we access f_pos
      // - use noop_llseek if we know we don't access f_pos,
      //   but we still want to allow users to call lseek
      //
      @ open1 exists @
      identifier nested_open;
      @@
      nested_open(...)
      {
      <+...
      nonseekable_open(...)
      ...+>
      }
      
      @ open exists@
      identifier open_f;
      identifier i, f;
      identifier open1.nested_open;
      @@
      int open_f(struct inode *i, struct file *f)
      {
      <+...
      (
      nonseekable_open(...)
      |
      nested_open(...)
      )
      ...+>
      }
      
      @ read disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      <+...
      (
         *off = E
      |
         *off += E
      |
         func(..., off, ...)
      |
         E = *off
      )
      ...+>
      }
      
      @ read_no_fpos disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ write @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      <+...
      (
        *off = E
      |
        *off += E
      |
        func(..., off, ...)
      |
        E = *off
      )
      ...+>
      }
      
      @ write_no_fpos @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ fops0 @
      identifier fops;
      @@
      struct file_operations fops = {
       ...
      };
      
      @ has_llseek depends on fops0 @
      identifier fops0.fops;
      identifier llseek_f;
      @@
      struct file_operations fops = {
      ...
       .llseek = llseek_f,
      ...
      };
      
      @ has_read depends on fops0 @
      identifier fops0.fops;
      identifier read_f;
      @@
      struct file_operations fops = {
      ...
       .read = read_f,
      ...
      };
      
      @ has_write depends on fops0 @
      identifier fops0.fops;
      identifier write_f;
      @@
      struct file_operations fops = {
      ...
       .write = write_f,
      ...
      };
      
      @ has_open depends on fops0 @
      identifier fops0.fops;
      identifier open_f;
      @@
      struct file_operations fops = {
      ...
       .open = open_f,
      ...
      };
      
      // use no_llseek if we call nonseekable_open
      ////////////////////////////////////////////
      @ nonseekable1 depends on !has_llseek && has_open @
      identifier fops0.fops;
      identifier nso ~= "nonseekable_open";
      @@
      struct file_operations fops = {
      ...  .open = nso, ...
      +.llseek = no_llseek, /* nonseekable */
      };
      
      @ nonseekable2 depends on !has_llseek @
      identifier fops0.fops;
      identifier open.open_f;
      @@
      struct file_operations fops = {
      ...  .open = open_f, ...
      +.llseek = no_llseek, /* open uses nonseekable */
      };
      
      // use seq_lseek for sequential files
      /////////////////////////////////////
      @ seq depends on !has_llseek @
      identifier fops0.fops;
      identifier sr ~= "seq_read";
      @@
      struct file_operations fops = {
      ...  .read = sr, ...
      +.llseek = seq_lseek, /* we have seq_read */
      };
      
      // use default_llseek if there is a readdir
      ///////////////////////////////////////////
      @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier readdir_e;
      @@
      // any other fop is used that changes pos
      struct file_operations fops = {
      ... .readdir = readdir_e, ...
      +.llseek = default_llseek, /* readdir is present */
      };
      
      // use default_llseek if at least one of read/write touches f_pos
      /////////////////////////////////////////////////////////////////
      @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read.read_f;
      @@
      // read fops use offset
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = default_llseek, /* read accesses f_pos */
      };
      
      @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ... .write = write_f, ...
      +	.llseek = default_llseek, /* write accesses f_pos */
      };
      
      // Use noop_llseek if neither read nor write accesses f_pos
      ///////////////////////////////////////////////////////////
      
      @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      identifier write_no_fpos.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ...
       .write = write_f,
       .read = read_f,
      ...
      +.llseek = noop_llseek, /* read and write both use no f_pos */
      };
      
      @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write_no_fpos.write_f;
      @@
      struct file_operations fops = {
      ... .write = write_f, ...
      +.llseek = noop_llseek, /* write uses no f_pos */
      };
      
      @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      @@
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = noop_llseek, /* read uses no f_pos */
      };
      
      @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      @@
      struct file_operations fops = {
      ...
      +.llseek = noop_llseek, /* no read or write fn */
      };
      ===== End semantic patch =====
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Julia Lawall <julia@diku.dk>
      Cc: Christoph Hellwig <hch@infradead.org>
      6038f373
  8. 07 10月, 2010 1 次提交
    • D
      Fix IRQ flag handling naming · df9ee292
      David Howells 提交于
      Fix the IRQ flag handling naming.  In linux/irqflags.h under one configuration,
      it maps:
      
      	local_irq_enable() -> raw_local_irq_enable()
      	local_irq_disable() -> raw_local_irq_disable()
      	local_irq_save() -> raw_local_irq_save()
      	...
      
      and under the other configuration, it maps:
      
      	raw_local_irq_enable() -> local_irq_enable()
      	raw_local_irq_disable() -> local_irq_disable()
      	raw_local_irq_save() -> local_irq_save()
      	...
      
      This is quite confusing.  There should be one set of names expected of the
      arch, and this should be wrapped to give another set of names that are expected
      by users of this facility.
      
      Change this to have the arch provide:
      
      	flags = arch_local_save_flags()
      	flags = arch_local_irq_save()
      	arch_local_irq_restore(flags)
      	arch_local_irq_disable()
      	arch_local_irq_enable()
      	arch_irqs_disabled_flags(flags)
      	arch_irqs_disabled()
      	arch_safe_halt()
      
      Then linux/irqflags.h wraps these to provide:
      
      	raw_local_save_flags(flags)
      	raw_local_irq_save(flags)
      	raw_local_irq_restore(flags)
      	raw_local_irq_disable()
      	raw_local_irq_enable()
      	raw_irqs_disabled_flags(flags)
      	raw_irqs_disabled()
      	raw_safe_halt()
      
      with type checking on the flags 'arguments', and then wraps those to provide:
      
      	local_save_flags(flags)
      	local_irq_save(flags)
      	local_irq_restore(flags)
      	local_irq_disable()
      	local_irq_enable()
      	irqs_disabled_flags(flags)
      	irqs_disabled()
      	safe_halt()
      
      with tracing included if enabled.
      
      The arch functions can now all be inline functions rather than some of them
      having to be macros.
      
      Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300]
      Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile]
      Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze]
      Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM]
      Acked-by: NThomas Gleixner <tglx@linutronix.de>
      Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR]
      Acked-by: Tony Luck <tony.luck@intel.com> [IA-64]
      Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R]
      Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU]
      Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS]
      Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC]
      Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC]
      Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390]
      Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score]
      Acked-by: Matt Fleming <matt@console-pimps.org> [SH]
      Acked-by: David S. Miller <davem@davemloft.net> [Sparc]
      Acked-by: Chris Zankel <chris@zankel.net> [Xtensa]
      Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha]
      Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300]
      Cc: starvik@axis.com [CRIS]
      Cc: jesper.nilsson@axis.com [CRIS]
      Cc: linux-cris-kernel@axis.com
      df9ee292
  9. 06 10月, 2010 1 次提交
    • L
      modules: Fix module_bug_list list corruption race · 5336377d
      Linus Torvalds 提交于
      With all the recent module loading cleanups, we've minimized the code
      that sits under module_mutex, fixing various deadlocks and making it
      possible to do most of the module loading in parallel.
      
      However, that whole conversion totally missed the rather obscure code
      that adds a new module to the list for BUG() handling.  That code was
      doubly obscure because (a) the code itself lives in lib/bugs.c (for
      dubious reasons) and (b) it gets called from the architecture-specific
      "module_finalize()" rather than from generic code.
      
      Calling it from arch-specific code makes no sense what-so-ever to begin
      with, and is now actively wrong since that code isn't protected by the
      module loading lock any more.
      
      So this commit moves the "module_bug_{finalize,cleanup}()" calls away
      from the arch-specific code, and into the generic code - and in the
      process protects it with the module_mutex so that the list operations
      are now safe.
      
      Future fixups:
       - move the module list handling code into kernel/module.c where it
         belongs.
       - get rid of 'module_bug_list' and just use the regular list of modules
         (called 'modules' - imagine that) that we already create and maintain
         for other reasons.
      Reported-and-tested-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Adrian Bunk <bunk@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: stable@kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5336377d
  10. 10 9月, 2010 1 次提交
  11. 24 8月, 2010 2 次提交
    • M
      [S390] fix tlb flushing vs. concurrent /proc accesses · 050eef36
      Martin Schwidefsky 提交于
      The tlb flushing code uses the mm_users field of the mm_struct to
      decide if each page table entry needs to be flushed individually with
      IPTE or if a global flush for the mm_struct is sufficient after all page
      table updates have been done. The comment for mm_users says "How many
      users with user space?" but the /proc code increases mm_users after it
      found the process structure by pid without creating a new user process.
      Which makes mm_users useless for the decision between the two tlb
      flusing methods. The current code can be confused to not flush tlb
      entries by a concurrent access to /proc files if e.g. a fork is in
      progres. The solution for this problem is to make the tlb flushing
      logic independent from the mm_users field.
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      050eef36
    • S
      [S390] s390: fix build error (sys_execve) · 7af048dc
      Sebastian Ott 提交于
      fix this build error:
      arch/s390/kernel/process.c:272: error: conflicting types for 'sys_execve'
      arch/s390/kernel/entry.h:45: error: previous declaration of 'sys_execve' was here
      make[1]: *** [arch/s390/kernel/process.o] Error 1
      make: *** [arch/s390/kernel] Error 2
      
      introduced by d7627467Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      7af048dc
  12. 18 8月, 2010 1 次提交
    • D
      Make do_execve() take a const filename pointer · d7627467
      David Howells 提交于
      Make do_execve() take a const filename pointer so that kernel_execve() compiles
      correctly on ARM:
      
      arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type
      
      This also requires the argv and envp arguments to be consted twice, once for
      the pointer array and once for the strings the array points to.  This is
      because do_execve() passes a pointer to the filename (now const) to
      copy_strings_kernel().  A simpler alternative would be to cast the filename
      pointer in do_execve() when it's passed to copy_strings_kernel().
      
      do_execve() may not change any of the strings it is passed as part of the argv
      or envp lists as they are some of them in .rodata, so marking these strings as
      const should be fine.
      
      Further kernel_execve() and sys_execve() need to be changed to match.
      
      This has been test built on x86_64, frv, arm and mips.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Tested-by: NRalf Baechle <ralf@linux-mips.org>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d7627467
  13. 14 8月, 2010 1 次提交
  14. 13 8月, 2010 2 次提交
  15. 10 8月, 2010 1 次提交
  16. 28 7月, 2010 2 次提交
    • M
      [S390] etr: fix clock synchronization race · 33fea794
      Martin Schwidefsky 提交于
      The etr events switch-to-local and sync-check disable the synchronous clock
      and schedule a work queue that tries to get the clock back into sync.
      If another switch-to-local or sync-check event occurs while the work queue
      function etr_work_fn still runs the eacr.es bit and the clock_sync_word can
      become inconsistent because check_sync_clock only uses the clock_sync_word
      to determine if the clock is in sync or not. The second pass of the
      etr_work_fn will reset the eacr.es bit but will leave the clock_sync_word
      intact. Fix this race by moving the reset of the eacr.es bit into the
      switch-to-local and sync-check functions and by checking the eacr.es bit
      as well to decide if the clock needs to be synced.
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      33fea794
    • H
      [S390] Fix IRQ tracing in case of PER · f5cdac27
      Heiko Carstens 提交于
      In case user space is single stepped (PER) the program check handler
      claims too early that IRQs are enabled on the return path.
      Subsequent checks will notice that the IRQ mask in the PSW and
      what lockdep thinks the IRQ mask should be do not correlate and
      therefore will print a warning to the console and disable lockdep.
      
      Fix this by doing all the work within the correct context.
      Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      f5cdac27
  17. 27 7月, 2010 1 次提交
    • J
      timkeeping: Fix update_vsyscall to provide wall_to_monotonic offset · 7615856e
      John Stultz 提交于
      update_vsyscall() did not provide the wall_to_monotoinc offset,
      so arch specific implementations tend to reference wall_to_monotonic
      directly. This limits future cleanups in the timekeeping core, so
      this patch fixes the update_vsyscall interface to provide
      wall_to_monotonic, allowing wall_to_monotonic to be made static
      as planned in Documentation/feature-removal-schedule.txt
      Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Anton Blanchard <anton@samba.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Tony Luck <tony.luck@intel.com>
      LKML-Reference: <1279068988-21864-7-git-send-email-johnstul@us.ibm.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      7615856e