Kernel Traffic #275 by Zack Brown

[email protected] Sat, 02 Oct 2004 17:48:37 -0700
Newsgroups gmane.linux.kernel.kernel-traffic
Message-ID <[email protected]>
                        Kernel Traffic #275 For 2 Oct 

                                 By Zack Brown

Table Of Contents

  * Standard Format
  * Text Format
  * XML Source
  * Threads Covered

    1.  15 Aug  - 19 Aug  (20    New blktool Tool To Replace hdparm
                          posts)
    2.  15 Aug  - 24 Aug  (13    New waitid() System Call For POSIX Conformance
                          posts) (Or Improvement)
    3.  16 Aug  - 19 Aug  (38    Linux 2.6.8.1-mm1 Released
                          posts)
    4.  17 Aug  - 19 Aug  (8     Some ext3 Documentation Updates
                          posts)
    5.  18 Aug  - 20 Aug  (7     VFS Mount Option Extensions
                          posts)
    6.  18 Aug  - 19 Aug  (3     dmraid Version 1.0.0-rc3 Released
                          posts)
    7.  18 Aug  - 20 Aug  (5     Manuel Estrada Sainz, Firmware Loader
                          posts) Maintainer, Deceased
    8.  19 Aug  - 25 Aug  (47    Linux 2.6.8.1-mm2 Released; Includes Reiser4
                          posts)
    9.  19 Aug            (1     Gamma DRM Driver To Be Dropped From The Kernel
                          post)
    10. 19 Aug  - 25 Aug  (16    Cleaning Up #include Statements In 2.6;
                          posts) Stability Not Necessarily Top Priority
    11. 20 Aug  - 24 Aug  (49    Linux 2.6.8.1-mm3 Released; Successfully Boots
                          posts) On A 512-CPU Altix
    12. 22 Aug  - 26 Aug  (44    Linux 2.6.8.1-mm4 Released; Andrew Describes
                          posts) Some Patch Submission Policy
    13. 24 Aug            (1     rng-tools Updated
                          post)

 

1. New blktool Tool To Replace hdparm
15 Aug  - 19 Aug  (20 posts) Archive Link: "new tool: blktool"
Topics: Disk Arrays: RAID, Disks: IDE, Disks: SCSI, Version Control
People: Jeff Garzik, Alan Cox

Jeff Garzik said:

    I just posted "blktool" on my SF page, http://sourceforge.net/projects/
    gkernel/ and in BitKeeper at bk://gkernel.bkbits.net/blktool

    blktool aims to be an easier to use, and more generic version of the
    existing utility 'hdparm'. For example,

            $ hdparm -c1 /dev/hda
                    becomes
            $ blktool /dev/hda pio-data 32-bit

            and

            $ hdparm -L0 /dev/hda
                    becomes
            $ blktool /dev/hda media unlock

    The utility is currently still fairly specific to IDE devices (as hdparm
    is), but that will change in the coming weeks as SCSI, I2O, and possibly
    some bits of hardware RAID control are added.

    The audience for this application, like hdparm, is fairly narrow, specific
    to people who tweak their storage devices and _know what they are doing_.
    Improper use of this tool, like hdparm, can turn your disk into a doorstop.

Alan Cox objected to the command line format, saying, "So you've replaced
hdparm's weird but unixish command line with an even more demented non linuxish
one that doesn't handle regexps for drive names?" He suggested a '--option=
value' format. Jeff said he preferred his original mechanism because it seemed
to have more structure, especially as the list of potential commands grew
larger. But he said he could also implement Alan's preference as well.

There seemed some general agreement that Jeff's basic idea was sound; and folks
started hacking on it.

 

2. New waitid() System Call For POSIX Conformance (Or Improvement)
15 Aug  - 24 Aug  (13 posts) Archive Link: "[PATCH] waitid system call"
Topics: BSD, POSIX
People: Roland McGrath, Andi Kleen

Roland McGrath said:

    This patch adds a new system call `waitid'. This is a new POSIX call that
    subsumes the rest of the wait* family and can do some things the older
    calls cannot. A minor addition is the ability to select what kinds of
    status to check for with a mask of independent bits, so you can wait for
    just stops and not terminations, for example. A more significant
    improvement is the WNOWAIT flag, which allows for polling child status
    without reaping. This interface fills in a siginfo_t with the same details
    that a SIGCHLD for the status change has; some of that info (e.g. si_uid)
    is not available via wait4 or other calls.

    I've added a new system call that has the parameter conventions of the
    POSIX function because that seems like the cleanest thing. This patch
    includes the actual system call table additions for i386 and x86-64; other
    architectures will need to assign the system call number, and 64-bit ones
    may need to implement 32-bit compat support for it as I did for x86-64. The
    new features could instead be provided by some new kludge inventions in the
    wait4 system call interface (that's what BSD did). If kludges are
    preferable to adding a system call, I can work up something different.

    I added a struct rusage field si_rusage to siginfo_t in the SIGCHLD case
    (this does not affect the size or layout of the struct). This is not part
    of the POSIX interface, but it makes it so that `waitid' subsumes all the
    functionality of `wait4'. Future kernel ABIs (new arch's or whatnot) can
    have only the `waitid' system call and the rest of the wait* family
    including wait3 and wait4 can be implemented in user space using waitid.
    There is nothing in user space as yet that would make use of the new field.

    Most of the new functionality is implemented purely in the waitid system
    call itself. POSIX also provides for the WCONTINUED flag to report when a
    child process had been stopped by job control and then resumed with
    SIGCONT. Corresponding to this, a SIGCHLD is now generated when a child
    resumes (unless SA_NOCLDSTOP is set), with the value CLD_CONTINUED in
    siginfo_t.si_code. To implement this, some additional bookkeeping is
    required in the signal code handling job control stops.

    The motivation for this work is to make it possible to implement the POSIX
    semantics of the `waitid' function in glibc completely and correctly. If
    changing either the system call interface used to accomplish that, or any
    details of the kernel implementation work, would improve the chances of
    getting this incorporated, I am more than happy to work through any issues.

Andi Kleen and others offered some criticism, and Roland posted an updated
patch the next day. Michael Kerrisk offered his criticism, particularly that
POSIX conformance might not be the best goal to have here. Michael said that
various other systems like Solaris and HP-UX had chosen to avoid full POSIX
compliance in this area. Roland asked for some more complete descriptions of
how these other systems behaved, and Michael provided some results of his
experiments. The discussion petered out at this point, but it seemed that
Roland was interested in possibly modifying his approach, if there were truly a
way to improve on POSIX in that case.

 

3. Linux 2.6.8.1-mm1 Released
16 Aug  - 19 Aug  (38 posts) Archive Link: "2.6.8.1-mm1"
Topics: Disk Arrays: RAID, Disks: IDE, Hot-Plugging, Kernel Release
Announcement, Profiling
People: Andrew Morton, Sam Ravnborg, Bartlomiej Zolnierkiewicz, Alan Cox, 
Bartlomiej

Andrew Morton announced Linux 2.6.8.1-mm1, saying:

    ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.8.1/
    2.6.8.1-mm1

      + perfctr is ready to be merged up, but there are concerns that it
        duplicates perfmon capabilities, and that perfmon may be a better base
        from which to start. Am waiting for the dust to settle on that front.
      + The packet-writing patches should be ready to go, but I haven't even
        looked at them yet, and am not sure that anyone else has reviewed the
        code.
      + Added the kprobes facility.

        Generally we prefer to not merge infrastructure into the kernel unless
        it has in-kernel users. kprobes is exceptional, in that its
        applications are all custom-written to solve a particular problem.

        One problem we face with kprobes is that there is no easy way in which
        it can receive runtime (or regression) testing.

        This patchset does include an application (a network packet tracer) but
        it's not obvious that we should retain that in the kernel.

      + This kernel probably still has the ia64 scheduler startup bug, although
        it works For Me.
      + If people have significant patches in here, please regression test them
        to make sure everything landed OK, thanks.

A bunch of folks reported bugs and other issues. Sam Ravnborg said:

    The following two patches can be dropped from -mm. The functionality has
    moved to scripts/mksysmap

    handle-undefined-symbols.patch
    Fail if vmlinux contains undefined symbols

    sparc32-ignore-undefined-symbols-with-3-or-more-leading-underscores.patch
    sparc32: ignore undefined symbols with 3 or more leading underscores

Bartlomiej Zolnierkiewicz also said that an ITE RAID driver patch in -mm should
not be pushed upstream, because "it duplicates _a lot_ of functionality present
in drivers/ide / libata (Alan Cox has native drivers/ide driver, although I
would still prefer libata based driver) and contains code for RAID metadata
handling which should belong to user-space." But Alan Cox replied:

    Some of the metadata handling is needed kernel side. I'm hoping we can
    avoid most of it with the drive hotplug code. The corner case causing the
    problem is when no arrays are configured so there is no device/hwif
    present.

    I looked at the libata stuff - it's part of the reason I sent Jeff the
    error dump/translate patch but right now libata is woefully ignorant of a
    large number of IDE/EIDE/ATA considerations.

 

4. Some ext3 Documentation Updates
17 Aug  - 19 Aug  (8 posts) Archive Link: "[RFC] ext3 documentation (lack of)"
Topics: Access Control Lists, FS: ext3
People: Diego Calleja

Diego Calleja said, "Lots of people think that ext3 is very slow. While I'm not
claiming that ext3 is the fatest fs in the world, I told some people to look at
Documentation/filesystem/ext3.txt and try to tweak it before doing some
benchmarks. To my surprise, several ext3 mount options were not documented (not
even in the source) except in some sites spread across the internet, so it's
not a surprise that lots of people ignores some mount options when doing
benchmarks, like the commit interval." He posted a documentation patch, saying,
"This documents commit (or it tries, sorry for my english), groups the
journal-related options in the same place of the document and adds other mount
options without documenting them (like the ones related to acl, xattr,
resizing, reservations, barriers)." Various folks offered suggestions and
further data, which Diego collected and converted into new versions of the
document. These he posted throughout the discussion.

 

5. VFS Mount Option Extensions
18 Aug  - 20 Aug  (7 posts) Archive Link: "[PATCH] Bind Mount Extensions 0.05"
People: Herbert Poetzl, Christoph Hellwig

Herbert Poetzl said, "The following patch extends the 'noatime', 'nodiratime'
and last but not least the 'ro' (read only) mount option to the vfs --bind
mounts, allowing them to behave like any other mount, by honoring those mount
flags (which are silently ignored by the current implementation in 2.4.x and
2.6.x)" . Several folks expressed a lot of interest in getting this patch into
the main kernel tree; but Christoph Hellwig said the patch had problems with
its interface, and would not be accepted in its current form. The feature, he
affirmed, was good; and he expected to see it in the main kernel within a year;
though perhaps not in the 2.6 timeframe.

 

6. dmraid Version 1.0.0-rc3 Released
18 Aug  - 19 Aug  (3 posts) Archive Link: "*** Announcement: dmraid 1.0.0-rc3
***"
Topics: Disk Arrays: RAID
People: Heinz Mauelshagen

Heinz Mauelshagen said:

    dmraid 1.0.0-rc3 is available at http://people.redhat.com:/~heinzm/sw/
    dmraid/ in source, source rpm and i386 rpm.

    dmraid (Device-Mapper Raid tool) discovers, [de]activates and displays
    properties of software RAID sets (ie. ATARAID) and contained DOS partitions
    using the device-mapper runtime of the 2.6 kernel.

    The following ATARAID types are supported on Linux 2.6:

    Highpoint HPT37X
    Highpoint HPT45X
    Intel Software RAID
    Promise FastTrack
    Silicon Image Medley

    This ATARAID type is only basically supported in this version (I need
    better metadata format specs; please help): LSI Logic MegaRAID

    Please provide insight to support those metadata formats completely.

    Thanks.

    See files README and CHANGELOG, which come with the source tarball for
    prerequisites to run this software, further instructions on installing and
    using dmraid!

 

7. Manuel Estrada Sainz, Firmware Loader Maintainer, Deceased
18 Aug  - 20 Aug  (5 posts) Archive Link: "[PATCH] Firmware Loader is orphan"
Topics: CREDITS File
People: Jesse Barnes, Horst von Brand

Ram?on Rey Vicente said that Manuel Estrada Sainz, the kernel firmware loader
maintainer, had died that May. He posted a patch to list the feature as
orphaned, and asked if anyone else was going to maintain it. Horst von Brand
offered his condolences; and folks agreed to add Manuel to the CREDITS file
along with the late Leonard Zubkoff. Jesse Barnes remarked, "Adding the fact
that they're deceased is probably a good idea, lest people email them, expect a
response and try to flame them or something (as happened recently with Leonard
iirc)."

 

8. Linux 2.6.8.1-mm2 Released; Includes Reiser4
19 Aug  - 25 Aug  (47 posts) Archive Link: "2.6.8.1-mm2"
Topics: Compression, FS: ReiserFS, FS: ext2, Kernel Release Announcement
People: Andrew Morton, Ryan Cumming, Rik van Riel, Hans Reiser, Tony Luck, 
Chris Wedgwood, William Lee Irwin III

Andrew Morton announced Linux kernel 2.6.8.1-mm2, saying:

    ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.8.1/
    2.6.8.1-mm2/

      + Added Tony Luck's ia64 devel tree to the -mm "external trees" lineup.
      + The monster memory leak which some people were seeing with audio CD
        writing should be fixed.
      + If your floppy drives magically disappear, try booting with floppy=
        no_acpi and send a report.
      + Added the reiser4 filesystem. Please give it a whizz. Please Cc
        [email protected] on any problem reports. (It spits a bunch of
        warnings on 64-bit compiles - that'll be fixed)

        Here's a little questionnaire which Hans filled out for me, to help
        people get started:

          o A really short guide to how to get up and running with this
            filesystem.

                Reiser4 is a file system based on dancing tree algorithms, and
                is described at http://www.namesys.com. One should be able to
                get it up and running just like any of the other filesystems
                supported by Linux. Configure it to be compiled either builtin
                or as a module. Create reiser4 filesystem with mkfs.reiser4,
                mount and use it. More detailed info can be found at http://
                thebsh.namesys.com/snapshots/LATEST/READ.ME.

          o The direct URL which people use to obtain the mkfs tool for this
            filesystem. Also fsck and anything else.

                Reiser4 userland tools can be obtained at ftp://ftp.namesys.com
                /pub/reiser4progs. ftp://ftp.namesys.com/pub/reiser4progs/
                README contains detailed instructions on how to compile and
                install these tools. Also all reiser4 progs have man pages.

          o Any known shortcomings, caveats, etc.

                Reiser4 has been tested on i386 yet only. Quota support is not
                ready yet. Should be ready soon. Reiser4 was tested
                extensively, and we got to where the mailing list was not able
                to hit any bugs, but then we told people that, got an order of
                magnitude increase in users, and they are able to hit bugs that
                we are working on now.

                Reiser's Law of Software Engineering: Each order of magnitude
                increase in users finds more bugs, in a quantity equal to the
                previous order of magnitude increase in users. Success for
                software developers is measured by how long the frustration
                lasts.

                Only the very core functionality is working. Exotic plugins, an
                API for multiple operation transactions and accessing multiple
                small files in one syscall, compression, inheritance, all have
                been postponed until after the core functionality is shipped.
                The compression plugin needs a code review before anyone should
                use it.

          o A statement on compatibility with reiserfs3 filesytems.

                To upgrade from reiserfs V3 to V4, use tar, or sponsor us to
                write a convertfs.

          o Bear in mind that people will immediately benchmark this filesytem,
            and first impressions count. Now is your chance to communicate any
            tuning guidelines, mount options or whatever which you'd like
            people to understand BEFORE they start publishing benchmark info.

                Reiser4 is not tuned for fsync/sync/O_SYNC performance yet.

                If you see results that are much different from those at
                www.namesys.com/benchmarks.html, let us know. If you see
                performance characteristics that don't quite make sense, email
                [email protected], such things are always of interest.

                reiser4 is not tuned for mmaping and dirtying more than
                physical ram like IOzone does. This is quite different in its
                code path from writing and dirtying more than physical ram.
                There are those who think that what IOZone does is rarely done
                by real programs, and therefor we should not bother to optimize
                what it does. All I know is, this month we are not optimized
                for it.

                Please consider its space savings when you benchmark it also.

Ryan Cumming took umbrage at the language of the ReiserFS help text. He quoted
the help text, "ReiserFS V3 is the stablest Linux filesystem, and V4 is the
fastest. In regards to claims by ext2 that they are the de facto standard Linux
filesystem, the most polite thing to say is that many persons disagree, and it
is interesting that those persons seem to include the distros that are growing
in market share. See http://www.namesys.com/benchmarks.html for why many
disagree." Ryan said, "These statements seem inflammatory at best, and bloat an
already large help text. Looks like it could use a little editing." Chris
Wedgwood said that this was just 'Hans-speak', and that folks who didn't like
it should just ignore it.

Rik van Riel took a look at the ReiserFS code and had some problems with it. He
said:

    The reiser 4 system call sys_reiserfs seems to need an additional patch,
    which is craftily hidden inside reiser4-only.patch

    That patch creates fs/reiser4/linux-5_reiser4_syscall.patch, which I can
    only assume reiser 4 users should apply...

    Kind of ugly.

    Looking further, the horrors only increase. It looks like sys_reiser4() is
    an interface to load programs into the kernel, with reiserfs4 containing an
    interpreter.

    I'll leave aside the issues of having a scripting language inside the
    kernel, since I'm sure other people will comment on it.

    However, I am absolutely flabbergasted that Hans Reiser is using a syscall
    here, instead of a filesystem interface.

    Furthermore, why do the parsing in the kernel, instead of compiling the
    human-readable strings in userspace and loading something easy to use into
    the kernel, like the selinux subsystem does?

    Since this code is bound to be horribly controversial, it may be an idea to
    remove this from the reiserfs4 core patch. That way the battles over the
    filesystem, and its interactions with the rest of the kernel can be fought
    first, without having the whole reiserfs4 filesystem strand in the
    quicksand of "why do we need an interpreted language with completely new
    filesystem semantics in the kernel?"

William Lee Irwin III was also troubled by having a scripting language in the
kernel, but there was no further discussion on that point. Close by, regarding
the sys_reiser4() system call, Andrew said:

    It's my understanding that sys_reiser4() is basically defunct at this
    point.

    It will probably be revived at some time in the future but we'd be best off
    crossing that bridge when we arrive at it, and ignoring the syscall part of
    the code at this time.

    For review purposes it would be better if the syscall code and all the
    namesys debug support code simply weren't present in the patch. But one can
    sympathise with the need to keep it there for the time being. Please just
    read around it.

Rik agreed that ignoring that section of the patch would work for him; and was
relieved that the system call was, for the moment, not in use. Hans Reiser also
responded to Andrew, saying that 'defunct' was not such an accurate description
of the situation. He offered:

    I would say unfinished and in need of a code review by me before anyone
    starts using it, instead of defunct. There is no good reason for it to be
    sent to Andrew as a patch file, and the guy responsible is on vacation.
    What it should be in as is an experimental do not touch config option
    turned off by default.

    sys_reiser4 is needed for these purposes:

      + to eliminate the (otherwise valid) argument that it is more performance
        efficient for attributes to be accessed via an API that is different
        from files, by allowing multiple files to be accessed in one system
        call
      + to bundle multiple filesystem operations into one atomic write
      + to prepare the groundwork for the semantic enhancements described in
        www.namesys.com/whitepaper.html (http://www.namesys.com/whitepaper.html
        )
      + to define a standard interface that users will find uniform across all
        apps for this functionality
      + to allow VFS to remain undisturbed in the eyes of legacy apps while
        semantic enhancements go into the filesystem namespace in a form that
        is less crippled by compatibility issues.

    Now that the core reiser4 functionality is stable, the lead programmers and
    I can spare some time to review sys_reiser4 and the compression plugin
    (also not yet ready for prime time). This will take us 6-12 weeks I would
    guess, as Digeo is keeping us 50% busy with work that earns our paychecks
    at the moment, darpa is also keeping me busy with www.namesys.com/
    blackbox.html (http://www.namesys.com/blackbox.html) , and I expect there
    will be a few bugs found in the core code over the next few months also.

 

9. Gamma DRM Driver To Be Dropped From The Kernel
19 Aug  (1 post) Archive Link: "gamma drm driver.."
People: Dave Airlie

Dave Airlie said if the Gamma DRM kernel driver:

    After a bit of discussion on the dri lists, we have come to the decision
    that it is probably necessary to retire the above driver, no dri developer
    is currently using the above hardware and the driver is so different from
    the others it makes a lot of hacks in the drm needed...

    If anyone does actually use this driver and hardware let us know or it'll
    be marked as BROKEN soon and then it will actually break :-)

 

10. Cleaning Up #include Statements In 2.6; Stability Not Necessarily Top
Priority
19 Aug  - 25 Aug  (16 posts) Archive Link: "includes cleanup."
People: Dave Jones, William Lee Irwin III, Tim Schmielau

Dave Jones said:

    I noticed that every file that could be built as a module was sucking in
    sched.h (and therefore, every other include file under the sun).

    This patch

      + removes the sched.h from module.h
      + Moves the capable() definition from sched.h to capability.h
      + split out the wake_up_* stuff to linux/wakeup.h
      + Removed sched.h includes from a bunch of drivers that didn't need it
        due to the above work.
      + Fixes up all the breakage I was able to find under x86. Fixing other
        arch's is simple enough, they just need to include sched.h explicity in
        a few places now (or jiffies.h, or capability.h or wakeup.h))

    I've not done any measurements to see if this is noticable on a compile, as
    I'd expect it to be mostly in the noise anyway (though last time I did this
    in 2.5.early, it did shave off the best part of a minute off my
    worst-case-scenario build), but untangling the spaghetti of includes a
    little should at least mean gcc uses less memory during the build.

William Lee Irwin III remarked, "sched.h is such an extreme garbage can header
I wouldn't mind seeing the whole thing torn completely apart. Every little
trimming is good. =)" Some days later he replied to himself:

    I hereby declare open season on linux/sched.h!

    In preparation for moving all user-related bits out of sched.h and coopting
    linux/user.h for this purpose, this patch converts all inclusions of linux/
    user.h to asm/user.h

Tim Schmielau got into it, posting a huge patch and replying:

    OK, let's go! ;-)

    Let's see how often we can kill it's include lines. To start from a clean
    base, I looked at vanilla 2.6.8.1 first before trying out your patches.

    analysis was i386-only, my personal config builds, allyesconfig does not
    (neither does it with an unpatched kernel)

There was no actual discussion during the rest of the thread, but William
posted several additional patches as well, all fairly invasive. At one point
Tim remarked, "I've postponed my work in late 2.5 for 2.7, but with the new
development model it seems we are asked to destabilize 2.6 instead ;-)"

 

11. Linux 2.6.8.1-mm3 Released; Successfully Boots On A 512-CPU Altix
20 Aug  - 24 Aug  (49 posts) Archive Link: "2.6.8.1-mm3"
Topics: Framebuffer, Hot-Plugging, Kernel Release Announcement
People: Andrew Morton, Jesse Barnes, Nick Piggin, William Lee Irwin III

Andrew Morton announced Linux 2.6.8.1-mm3, saying:

    ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.8.1/
    2.6.8.1-mm3/

      + Added three more bk trees:

        bk-fb: Some ARM framebuffer driver (rmk)
        bk-mmc: ARM-specific media drivers(?)
        bk-watchdog: watchdog drivers

      + I'm totally unclear on what's happening with the release_task
        sleep-while-atomic bug, and with the CPU hotplug BUG. This kernel will
        probably emit might_sleep warnings. Turn off CONFIG_PREEMPT if it gets
        irritating.
      + Added Nick Piggin's CPU scheduler to see what happens. See inside the
        patch for details. Please test, benchmark, report.
      + This is (very) lightly tested. Mainly a resync with various parties.

There were various bug reports and other issues, and Jesse Barnes also remarked
at one point, "Woo-hoo! This boots *without changes* on a 512p Altix! Now to
re-run the profiles and try wli's new per-cpu profiling buffers." He replied to
himself an hour later, "I applied wli's" [William Lee Irwin III's] "per-cpu
profiling patch, added some tweaks that he and I discussed on irc and things
look pretty good. We can now profile all 512 CPUs in the system w/o livelocking
:)" He posted some performance stats, and various folks debated the merits.

 

12. Linux 2.6.8.1-mm4 Released; Andrew Describes Some Patch Submission Policy
22 Aug  - 26 Aug  (44 posts) Archive Link: "2.6.8.1-mm4"
Topics: Kernel Release Announcement, Kexec, Version Control
People: Andrew Morton, William Lee Irwin III

Andrew Morton announced Linux 2.6.8.1-mm4, saying:

    ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.8.1/
    2.6.8.1-mm4/

      + Added the kexec code. Again. This was in -mm a year or so ago but
        didn't make it.
      + This kernel has an x86 patch which alters the copy_*_user() functions
        so they will return -EFAULT on a fault rather than the number of bytes
        which remain to be copied. This is a bit of an experiment, because this
        seems to be the preferred API for those functions. It's a
        see-what-breaks thing.

        And things will break. If weird behaviour is observed, please revert
        usercopy-return-EFAULT.patch and send a report.

In the course of various sub-discussions, William Lee Irwin III posted a patch
and Andrew said:

    I'd prefer it if you (and everyone else) could give a meaningful
    English-language Subject: to patches, please.

    A well-chosen patch Subject: becomes a sort of globally-unique key by which
    the patch is tracked - I munge it into a patch filename and it propagates
    all the way into bitkeeper. It can be used for searching email folders,
    googling, inter-developer discussion, etc, etc.

Tim Bird leaped onto this one, patching the Documentation/SubmittingPatches to
quote Andrew's email.

 

13. rng-tools Updated
24 Aug  (1 post) Archive Link: "rng-tools updated"
Topics: Random Number Generation
People: Jeff Garzik

Jeff Garzik said:

    Just posted version 2 of rng-tools at http://sourceforge.net/projects/
    gkernel/

    This release fixes a problem related to 2.6.x kernels.

    rng-tools is currently for users of hardware random number generators
    (RNGs), and the included daemon rngd fill the kernel entropy pool from
    userspace with the results of the output.

    Future directions include:

      + support for VIA 'xcrypt' instruction in userspace, avoiding the need
        for a kernel driver
      + multithreaded daemon
      + additional entropy sources besides the dedicated h/w RNG

 

 

 

 

 

 

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