- 07 2月, 2008 40 次提交
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由 Richard Kennedy 提交于
Here's a couple of small additions to BUG-HUNTING. 1. point out that you can list code in gdb with only one command (gdb) l *(<symbol> + offset) 2. give a very brief hint how to decode module symbols in call traces Signed-off-by: NRichard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Karsten Wiese 提交于
schedule_timeout(jiffies) waits for at least jiffies - 1. Add 1 jiffie to the timeout_jiffies calculated in sys_poll() to wait at least timeout_msecs, like poll() manpage says. Signed-off-by: NKarsten Wiese <fzu@wemgehoertderstaat.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joe Peterson 提交于
Fix two N_TTY line discipline issues related to resuming a stopped TTY (typically done with ctrl-S): 1) Fix handling of character that resumes a stopped TTY (with IXANY) With "stty ixany", the TTY line discipline would lose the first character after the stop, so typing, for example, "hi^Sthere" resulted in "hihere" (the 't' would cause the resume after ^S, but it would then be thrown away rather than processed as an input character). This was inconsistent with the behavior of other Unix systems. 2) Fix interrupt signal (e.g. ctrl-C) behavior in stopped TTYs With "stty -ixany" (often the default), interrupt signals were ignored in a stopped TTY until the TTY was resumed with the start char (typically ctrl-Q), which was inconsistent with the behavior of other Unix systems. Signed-off-by: NJoe Peterson <joe@skyrush.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
Just converting this documentation semaphore reference, since we don't want to promote semaphore usage. Signed-off-by: NDaniel Walker <dwalker@mvista.com> Acked-by: NCorey Minyard <minyard@acm.org> Cc: Greg KH <greg@kroah.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Eric Dumazet 提交于
We can use ilog2() in fs/namespace.c to compute hash_bits and hash_mask at compile time, not runtime. [akpm@linux-foundation.org: clean it all up] Signed-off-by: NEric Dumazet <dada1@cosmosbay.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Andrew Morton 提交于
- Account for debug_smp_processor_id()'s own preempt_disable() when displaying the preempt_count(). - 80 cols, not 800. Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Eric Dumazet 提交于
groups_sort() can be quite long if user loads a large gid table. This is because GROUP_AT(group_info, some_integer) uses an integer divide. So having to do XXX thousand divides during one syscall can lead to very high latencies. (NGROUPS_MAX=65536) In the past (25 Mar 2006), an analog problem was found in groups_search() (commit d74beb9f ) and at that time I changed some variables to unsigned int. I believe that a more generic fix is to make sure NGROUPS_PER_BLOCK is unsigned. Signed-off-by: NEric Dumazet <dada1@cosmosbay.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Adrian Bunk 提交于
Fix the following section mismatch with CONFIG_HOTPLUG=n, CONFIG_HOTPLUG_CPU=y: WARNING: vmlinux.o(.text+0x399a6): Section mismatch: reference to .init.text.5:idle_regs (between 'fork_idle' and 'get_task_mm') Signed-off-by: NAdrian Bunk <bunk@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Adrian Bunk 提交于
calibrate_delay() must be __cpuinit, not __{dev,}init. I've verified that this is correct for all users. While doing the latter, I also did the following cleanups: - remove pointless additional prototypes in C files - ensure all users #include <linux/delay.h> This fixes the following section mismatches with CONFIG_HOTPLUG=n, CONFIG_HOTPLUG_CPU=y: WARNING: vmlinux.o(.text+0x1128d): Section mismatch: reference to .init.text.1:calibrate_delay (between 'check_cx686_slop' and 'set_cx86_reorder') WARNING: vmlinux.o(.text+0x25102): Section mismatch: reference to .init.text.1:calibrate_delay (between 'smp_callin' and 'cpu_coregroup_map') Signed-off-by: NAdrian Bunk <bunk@kernel.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Richard Henderson <rth@twiddle.net> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Christian Zankel <chris@zankel.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Richard Knutsson 提交于
Fixing: CHECK kernel/params.c kernel/params.c:329:41: warning: incorrect type in argument 8 (different signedness) kernel/params.c:329:41: expected int *num kernel/params.c:329:41: got unsigned int * Signed-off-by: NRichard Knutsson <ricknu-0@student.ltu.se> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Eric Dumazet 提交于
Actual code let compiler generates idiv instruction on x86. Using a right shift is OK here and readable as well. Before patch 10: 57 push %edi 11: 56 push %esi 12: 89 d6 mov %edx,%esi 14: 53 push %ebx 15: 89 c3 mov %eax,%ebx 17: eb 22 jmp 3b <search_extable+0x2b> 19: 89 f0 mov %esi,%eax 1b: ba 02 00 00 00 mov $0x2,%edx 20: 29 d8 sub %ebx,%eax 22: 89 d7 mov %edx,%edi 24: c1 f8 03 sar $0x3,%eax 27: 99 cltd 28: f7 ff idiv %edi 2a: 8d 04 c3 lea (%ebx,%eax,8),%eax 2d: 39 08 cmp %ecx,(%eax) ... After patch 00000010 <search_extable>: 10: 53 push %ebx 11: 89 c3 mov %eax,%ebx 13: eb 18 jmp 2d <search_extable+0x1d> 15: 89 d0 mov %edx,%eax 17: 29 d8 sub %ebx,%eax 19: c1 f8 04 sar $0x4,%eax 1c: 8d 04 c3 lea (%ebx,%eax,8),%eax 1f: 39 08 cmp %ecx,(%eax) ... Signed-off-by: NEric Dumazet <dada1@cosmosbay.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Petr Cvek 提交于
Add detection for IT87XX SuperIO chip and disabling its POST feature, which made noise on parallel port's pins. Signed-off-by: NPetr Cvek <petr.cvek@tul.cz> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nick Warne 提交于
Add the Dell UK 6400 Inspiron model (MM061) to allow the i8k module to load correctly without using 'force=1' Signed-off-by: N"Nick Warne" <nick@ukfsn.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Thomas Bogendoerfer 提交于
Use DEFAULT_SGI_PARTITION for SGI_PARTION default Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Christian Pellegrin 提交于
Fix wrong netmos 9855 serial port configuration. On loading only one serial port was present and it wasn't working. After looking in the data sheet I realized that the base address was wrong. For further reference here is lspci and relevant dmesg output: 02:00.0 Communication controller: NetMos Technology PCI 9855 Multi-I/O Controller (rev 01) (prog-if 02) Subsystem: LSI Logic / Symbios Logic Unknown device 0022 Flags: medium devsel, IRQ 19 I/O ports at df00 [size=8] I/O ports at de00 [size=8] I/O ports at dd00 [size=8] I/O ports at dc00 [size=8] I/O ports at db00 [size=8] I/O ports at da00 [size=16] parport1: PC-style at 0xdd00 [PCSPP,TRISTATE] parport2: PC-style at 0xdf00 [PCSPP,TRISTATE,EPP] 0000:02:00.0: ttyS0 at I/O 0xdb00 (irq = 19) is a 16550A 0000:02:00.0: ttyS1 at I/O 0xda00 (irq = 19) is a 16550A Signed-off-by: NChristian Pellegrin <chripell@fsfe.org> Cc: Thomas Richter <thor@math.TU-Berlin.DE> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Martin Schitter <ms@gewi.kfunigraz.ac.at> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Luís P Mendes 提交于
Added pci device id for the Quatech SPPXP-100 ExpressCard - 0x278 - to include/linux/pci_id.h Modified drivers/parport/parport_pc.c to support the Quatech SPPXP-100 Parallel port PCI ExpressCard [akpm@linux-foundation.org: build fix] Signed-off-by: NLuís P Mendes <luis.p.mendes@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nick Piggin 提交于
ext2 should not worry about checking sb->s_blocksize for XIP before the sb's blocksize actually gets set. Signed-off-by: NNick Piggin <npiggin@suse.de> Acked-by: NCarsten Otte <cotte@de.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
The port_write_mutex was converted from a semaphore to a mutex, but there was still this ifdef'd init_MUTEX reference remaining. Signed-off-by: NDaniel Walker <dwalker@mvista.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
[akpm@linux-foundation.org: cleanup] Signed-off-by: NDaniel Walker <dwalker@mvista.com> Acked-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Denis Cheng 提交于
Signed-off-by: NDenis Cheng <crquan@gmail.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Jeff Mahoney <jeffm@suse.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Denis Cheng 提交于
Signed-off-by: NDenis Cheng <crquan@gmail.com> Cc: Corey Minyard <minyard@acm.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
I converted some of the document to reflect mutex usage instead of semaphore usage. Since we shouldin't be promoting semaphore usage when it's on it's way out.. Signed-off-by: NDaniel Walker <dwalker@mvista.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joe Peterson 提交于
Turn on INTR/QUIT/SUSP echoing in the N_TTY line discipline (e.g. ctrl-C will appear as "^C" if stty echoctl is set and ctrl-C is set as INTR). Linux seems to be the only unix-like OS (recently I've verified this on Solaris, BSD, and Mac OS X) that does *not* behave this way, and I really miss this as a good visual confirmation of the interrupt of a program in the console or xterm. I remember this fondly from many Unixs I've used over the years as well. Bringing this to Linux also seems like a good way to make it yet more compliant with standard unix-like behavior. [akpm@linux-foundation.org: coding-style fixes] Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Roland McGrath 提交于
This adds support to allow asm/ptrace.h to define two new macros, arch_ptrace_stop_needed and arch_ptrace_stop. These control special machine-specific actions to be done before a ptrace stop. The new code compiles away to nothing when the new macros are not defined. This is the case on all machines to begin with. On ia64, these macros will be defined to solve the long-standing issue of ptrace vs register backing store. Signed-off-by: NRoland McGrath <roland@redhat.com> Cc: Petr Tesarik <ptesarik@suse.cz> Cc: Tony Luck <tony.luck@intel.com> Cc: Matthew Wilcox <willy@debian.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Jan Kara 提交于
We restarted scan of sb->s_inodes list whenever we had to drop inode_lock in add_dquot_ref(). This leads to overall quadratic running time and thus add_dquot_ref() can take several minutes when called on a life filesystem. We fix the problem by using the fact that inode cannot be removed from s_inodes list while we hold a reference to it and thus we can safely restart the scan if we don't drop the reference. Here we use the fact that inodes freshly added to s_inodes list are already guaranteed to have quotas properly initialized and the ordering of inodes on s_inodes list does not change so we cannot skip any inode. Thanks goes to Nick <gentuu@gmail.com> for analyzing the problem and testing the fix. [akpm@linux-foundation.org: iput(NULL) is legal] Signed-off-by: NJan Kara <jack@suse.cz> Cc: Nick <gentuu@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Denis Cheng 提交于
single list_head variable initialized with LIST_HEAD_INIT could almost always can be replaced with LIST_HEAD declaration, this shrinks the code and looks better. Signed-off-by: NDenis Cheng <crquan@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Corey Minyard <minyard@acm.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nick Piggin 提交于
Convert uio from nopage to fault. Signed-off-by: NNick Piggin <npiggin@suse.de> Acked-by: NHans J Koch <hjk@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nick Piggin 提交于
Convert relay from nopage to fault. Remove redundant vma range checks. Switch from OOM to SIGBUS if the resource is not available. Signed-off-by: NNick Piggin <npiggin@suse.de> Cc: Tom Zanussi <zanussi@us.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Paulo Marques 提交于
When resolving symbol names from addresses with aliased symbol names, kallsyms_lookup always returns the first symbol, even if it is a weak symbol. This patch changes this by sorting the symbols with the weak symbols last before feeding them to the kernel. This way the kernel runtime isn't changed at all, only the kallsyms build system is changed. Another side effect is that the symbols get sorted by address, too. So, even if future binutils version have some bug in "nm" that makes it fail to correctly sort symbols by address, the kernel won't be affected by this. Mathieu says: I created a module in LTTng that uses kallsyms to get the symbol corresponding to a specific system call address. Unfortunately, all the unimplemented syscalls were all referring to the (same) weak symbol identifying an unrelated system call rather that sys_ni (or whatever non-weak symbol would be expected). Kallsyms was dumbly returning the first symbol that matched. This patch makes sure kallsyms returns the non-weak symbol when there is one, which seems to be the expected result. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Looks-great-to: Rusty Russell <rusty@rustcorp.com.au> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
Convert the unix98 allocated_ptys_lock to a mutex. Signed-off-by: NDaniel Walker <dwalker@mvista.com> Acked-by: NIngo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
I couldn't find any users, so removing it.. Signed-off-by: NDaniel Walker <dwalker@mvista.com> Cc: Karsten Keil <kkeil@suse.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Walker 提交于
I couldn't find any users, so removing it.. Signed-off-by: NDaniel Walker <dwalker@mvista.com> Acked-by: NAlan Cox <alan@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Daniel Drake 提交于
Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: NDaniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nick Piggin 提交于
The inotify debugging code is supposed to verify that the DCACHE_INOTIFY_PARENT_WATCHED scalability optimisation does not result in notifications getting lost nor extra needless locking generated. Unfortunately there are also some races in the debugging code. And it isn't very good at finding problems anyway. So remove it for now. Signed-off-by: NNick Piggin <npiggin@suse.de> Cc: Robert Love <rlove@google.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Jan Kara <jack@ucw.cz> Cc: Yan Zheng <yanzheng@21cn.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nick Piggin 提交于
There is a race between setting an inode's children's "parent watched" flag when placing the first watch on a parent, and instantiating new children of that parent: a child could miss having its flags set by set_dentry_child_flags, but then inotify_d_instantiate might still see !inotify_inode_watched. The solution is to set_dentry_child_flags after adding the watch. Locking is taken care of, because both set_dentry_child_flags and inotify_d_instantiate hold dcache_lock and child->d_locks. Signed-off-by: NNick Piggin <npiggin@suse.de> Cc: Robert Love <rlove@google.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Jan Kara <jack@ucw.cz> Cc: Yan Zheng <yanzheng@21cn.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Thomas Bogendoerfer 提交于
New serial driver for SC2681/SC2691 uarts. Older SNI RM400 machines are using these chips for onboard serial ports. Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Torben Mathiasen <device@lanana.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Thomas Bogendoerfer 提交于
Use SGI_HAS_DS1286 for SGI_DS1286 depends Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Thomas Bogendoerfer 提交于
- Use SGI_HAS_ZILOG for IP22_ZILOG depends - remove IP22 from description, because the driver works on more than IP22 SGI machines Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Robert P. J. Day 提交于
Given that init/Makefile includes initramfs.c in the build only if CONFIG_BLK_DEV_INITRD is defined, there seems to be no point checking for it yet again. Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Paul E. McKenney 提交于
The rcu_assign_pointer() primitive currently unconditionally executes a memory barrier, even when a NULL pointer is being assigned. This has lead some to avoid using rcu_assign_pointer() for NULL pointers, which loses the self-documenting advantages of rcu_assign_pointer() This patch uses __builtin_const_p() to omit needless memory barriers for NULL-pointer assignments at compile time with no runtime penalty, as discussed in the following thread: http://www.mail-archive.com/netdev@vger.kernel.org/msg54852.html Tested on x86_64 and ppc64, also compiled the four cases (NULL/non-NULL and const/non-const) with gcc version 4.1.2, and hand-checked the assembly output. Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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