Kernel Traffic #180 For 18 Aug 2002

It's big, it's complex, and nobody seems to take it that seriously (the only people who ever asked _me_ about it was Intel, and they seem to have cancelled their own projects).

If it turns out to be a big hit, it can be backported. But as it looks now, it has very little relevance for any 2.6 freeze schedule.

True, and to second that with some facts, companies who were making this their mainstay, are in much pain, on top of their economic status, because of Intel seemingly cancelling their projects.

Several companies in Austin, TX were chomping at the bit for people to come work on Infiniband technology, but there has been nothing new relating to this climate for a very long time...and probably won't be unless Intel, HP, IBM, someone with deep pockets and a marketing machine can show it's viable for consumer use.

Ah, the austin rumor mill.

According to a friend of mine who works at AMD:

1. Intel licensed that hyper-transport thing when they licensed x86-64 (Yamhill?).
2. Dell gave people refunds on the few itanium machines they actually managed to sell. (I believe the number I heard was a total of about two hundred and fifty total itanium "development" systems sold...)

There would appear to be a distinct trend here, but you know rumors... :)

These are the valid parameters to the SIOCETHTOOL ioctl(). Network drivers should support these as much as possible.

ETHTOOL_GSET
ETHTOOL_SSET

Get/set NIC settings. These commands expect a 'struct ethtool_cmd *' argument. This struct includes fields for supported features (speed, duplex, transceiver), advertised features, speed, duplex, port, transceiver, and autonegotiation. If the caller attempts to set an invalid value for any field, return -EINVAL.

ETHTOOL_GDRVINFO

Get driver information. This command expects a 'struct ethtool_drvinfo *' argument. This struct includes the driver identifier as a string, the driver version as a string, bus information for the interface, and length information for other ETHTOOL_* commands.

ETHTOOL_GREGS

Get a register dump from the NIC. This command expects a 'struct ethtool_regs regs *' argument. This struct has a driver-specific version field and a length field. The length field indicates the length of the data field to be populated with register information.

ETHTOOL_GWOL
ETHTOOL_SWOL

Get/set wake-on-lan options for the NIC. These commands expect a 'struct ethtool_wolinfo *' argument. This struct has fields for supprted and active WoL options, and the SecureOn password, if active. If the caller attempts to set an invalid value, return -EINVAL.

ETHTOOL_GMSGLVL
ETHTOOL_SMSGLVL

Get/set the driver message-level value for the NIC. This command expects a 'struct ethtool_value *' argument.

ETHTOOL_NWAY_RST

Force auto-negotiation to restart, if it is enabled. If it is not enabled, return -EINVAL.

ETHTOOL_GLINK

Read the current link status. This command expects a 'struct ethtool_value *' argument.

ETHTOOL_GEEPROM
ETHTOOL_SEEPROM

Get/set EEPROM data. These commands expect a 'struct ethtool_eeprom *' argument. This struct has a magic number, an offset and length pair, and a data field. If the offset+length are longer than the maximum size, the extra is silently ignored.

ETHTOOL_GCOALESCE
ETHTOOL_SCOALESCE

Get/set coalescing parameters. These commands expect a 'struct ethtool_coalesce *' argument. This struct has several fields for configuring coalescing - see ethtool.h for details. If the caller attempts to set an invalid value, return -EINVAL.

ETHTOOL_GRINGPARAM
ETHTOOL_SRINGPARAM

Get/set RX/TX ring parameters. These commands expect a 'struct ethtool_ringparam *' aargument. This struct has fields for several rx pending options, and tx pending. If the caller attempts to set an invalid value, return -EINVAL.

ETHTOOL_GPAUSEPARAM
ETHTOOL_SPAUSEPARAM

Get/set the RX/TX pause parameters. These commands expect a 'struct ethtool_pauseparam *' argument. This struct has fields to enable autonegotiation of pause parameters and to force RX and TX pause control.

ETHTOOL_GRXCSUM
ETHTOOL_SRXCSUM

Get/set the RX hardware checksum capability/flag. These commands expect a 'struct ethtool_value *' argument. If the caller attempts to enable RX hardware checksumming on an interface that does not support it, return -EINVAL.

ETHTOOL_GTXCSUM
ETHTOOL_STXCSUM

Get/set the TX hardware checksum capability/flag. These commands expect a 'struct ethtool_value *' argument. If the caller attempts to enable TX hardware checksumming on an interface that does not support it, return -EINVAL.

ETHTOOL_GSG
ETHTOOL_SSG

Get/set the scatter/gather capability/flag. These commands expect a 'struct ethtool_value *' argument. If the caller attempts to set an invalid value, return -EINVAL.

ETHTOOL_TEST
/* execute NIC self-test, priv. */

ETHTOOL_GSTRINGS
/* get specified string set */

ETHTOOL_PHYS_ID
/* identify the NIC */

ETHTOOL_GSTATS
/* get NIC-specific statistics */

A series of driverfs changes went into Linus' tree last Friday. This is a short summary of those changes, and some notes on how to use them.

Firstly, I changed the name of the structure that must be declared from struct driver_file_entry to struct device_attribute. This more accurately represents what is going on.

I've also created a macro[1] for defining device attributes, that goes like this:

DEVICE_ATTR(name,"strname",mode,show,store);

This will create a structure by the name of 'dev_attr_##name', where ##name is the first parameter, which can then be passed to device_create_file(). [2]

The definition of device_remove_file has changed to:

void device_remove_file(struct device * dev, struct device_attribute * attr);

(The second parameter is now the same type as what is passed to device_create_file, for consistency's sake (instead of a char *)).

I've added support for bus and device driver attributes. The mechanism for manipulating them is analogous to that of device attributes. To declare them, you do:

BUS_ATTR(name,"strname",mode,show,store); DRIVER_ATTR(name,"strname",mode,show,store);

which create the objects

struct bus_attribute bus_attr_##name;

and

struct driver_attribute driver_attr_##name;

respectively.

You can then use

int bus_create_file(struct bus_type *, struct bus_attribute *); void bus_remove_file(struct bus_type *, struct bus_attribute *);

int driver_create_file(struct device_driver *, struct driver_attribute *); void driver_remove_file(struct device_driver *, struct driver_attribute *);

To add and remove them.

Bus attribute files appear in the bus's directory (bus/<bus>/ under the driverfs mountpoint).

Driver attributes appear in the driver's directory (bus/<bus>/<driver>/ under the driverfs mountpoint).

The bus show and store routines are identical to the device show and store routines, though they take a pointer of type struct bus_type as the first parameter.

Similarly for drivers; they take a struct device_driver * as the first parameter.

Please see include/linux/device.h for the structure definitions, and drivers/base/fs/*.c for implementation details.

driverfs now has the ability to support attributes for any object type. I've updated the documentation (Documentation/filesystems/driverfs.txt) to hopefully include enough information to hack on it. I'm also open to all questions and suggestions, so please feel free to ask.

NTFS: 2.0.24 - Cleanups.

• Treat BUG_ON() as ASSERT() not VERIFY(), i.e. do not use side effects inside BUG_ON(). (Adam J. Richter)
• Split logical OR expressions inside BUG_ON() into individual BUG_ON() calls for improved debugging. (Adam J. Richter)
• Add errors flag to the ntfs volume state, accessed via NVol{,Set,Clear}Errors(vol).
• Do not allow read-write remounts of read-only volumes with errors.
• Clarify comment for ntfs file operation sendfile which was added by Christoph Hellwig a while ago (just using generic_file_sendfile()) to say that ntfs ->sendfile is only used for the case where the source data is on the ntfs partition and the destination is somewhere else, i.e. nothing we need to concern ourselves with.

Just out of curiosity I tried it with

static void tg3_write_mailbox_reg32(struct tg3 *tp, u32 off, u32 val)
{ 
        unsigned long flags;

        spin_lock_irqsave(&tp->indirect_lock, flags);
        writel(val, tp->regs + off);
        spin_unlock_irqrestore(&tp->indirect_lock, flags);
}

and that plain works. That means that only the mailbox writes have additional locking around the otherwise unchanged writel() call. Does the spin_lock_irqsave/spin_unlock_irqrestore take care of the PCI ordering?

While loading properly, this still crashed the machine. After giving it some thought I tried to add a dummy pci_read_config_dword() just before the writel(), and that works! I use this function both for tw32 and tw32_mailbox. I hammered it over one hour with a script that crashed it always in five seconds, and not so much as a hiccup :-)

Only one question is left: can this effect be achieved more elegantly?

This patch allows tasks to share credentials via a flag to clone().

This version fixes the problem with exec() that Linus found. Tasks that call exec() get their own copy of the credentials at that point.

The URL is here because it's too big to include in email:

http://www.ibm.com/linux/ltc/patches/misc/cred-2.5.30-3.diff.gz

The patch is against Linus' BK tree as of this morning.

Macros (and inlined functions) have the advantage that they enforce good policy. Doing 'task->cred->uid = a' on tasks other than 'current' is in general not a very safe thing to do. This sort of issue w.r.t. safe policies should in particular be worrying you when you start adding CRED_CLONE...

There are good precedents for this sort of argument: see 'set_current_state()' & friends.

In addition, those macros would allow you to set up compatibility with 2.4.x and simplify patch backports.

As for changing the structure: As I said previously I'd like to unify all those { fsuid, fsgid, group } things into a proper ucred, so that we can share these objects around the VFS, and cache them... Your 'struct cred' as it stands will not suffice to do all that since it does not provide the necessary Copy On Write protection. (For instance if some thread temporarily raises my process privileges, I will *not* want all my already opened 'struct file's to suddenly gain root access).

Authentication under UNIX usually requires you to check the process' uid/gid/groups affiliation. As such, it is useful to be able to pass that information around the kernel. Most OSes use some variation of the BSD 'ucred' structure which is reference counted and obeys COW (copy on write).

struct ucred {
  atomic_t count;
  uid_t    uid;      /* == fsuid if you like */
  gid_t    gid;      /* == fsgid  "  "   "   */
  int      ngroups;
  gid_t    *groups;
};

This means that 'struct file', the underlying filesystems, whoever else... can hold a reference to the above structure and be assured that it will never change. Changing the fsuid etc. are extremely rare operations compared to opening/closing a file, so the whole idea is precisely to *avoid* having to copy the above information all the time (which, given all the races that CLONE_CRED introduces, is a good thing).

As for POSIX behaviour: it is quite compatible with the above. The only change would be that your shared 'struct cred' would require a reference to a struct ucred rather than including fsuid, fsgid, groups as cred structure members.

Note: Given that Linux has adopted the 'capability' model on top of the standard UNIX authentication model, it might perhaps be necessary to move the capabilities into the ucred in order to make them COW too?

What if one thread is doing an RPC call while the other is changing the 'groups' entry?

Given that the first thread wants both to copy and/or compare the groups entry what prevents scenarios of the form?

  Thread 1                       Thread 2

                                change cred->ngroups
  copy cred->ngroups
  copy cred->groups
                                change cred->groups

Please don't do this with locking, I really think the right thing to do is to have a "duplicate()" function, and when you pass credentials off to something, you dup them at that point.

If you start off as non-root, and then execve suid into root, a pending NFS request should _not_ suddently have the credentials changed under it. Yet clearly that kind of thing can't just be locked either.

Along with copy-on-write semantics, this should perform perfectly well (ie "duplicate()" would only increment a count, and then setuid() would have to have code soemthing like

        if (cred->count > 1) {
                newcred = alloc_cred();
                copy_cred(newcred, cred);
                for_each_cred_group(p) {
                        p->cred = newcred;
                        atomic_inc(&newcred->count);
                        putcred(cred);
                }
        }

instead.

The Linux Test Project test suite LTP-20020807.tgz has been released. Visit our website ( http://ltp.sourceforge.net ) to download the latest version of the test suite, and for information on test results on pre-release, release candidate and stable releases of the kernel. There is also a list of test cases that are expected to fail, please find the list at http://ltp.sourceforge.net/expected-errors.php.

Highlights

• LTP's Kernel Code Coverage website for 2.5.X kernel is live http://ltp.sf.net/coverage/coverage-2.5.26/index.html
• Kernel code coverage tools are available on CVS under module utils
• Automated test frame work to extract, build and install various Linux tests are available on CVS under module utils
• Database stress tool 'dbgrinder' is available on cvs under ltp/utils/database

We encourage the community to post results, patches or new tests on our mailing list and use the CVS bug tracking facility to report problems that you might encounter with the test suite. More details are available at our web-site.

Change Log

• New Additions
• Added new test-cases for link07,fcntl22,link06 ( Group Bull )
• Added Linux kernel scheduler latency tester ( Davide Libenzi )
• Database test tool 'dbgrinder' ( James Kenefick )
• Fixes
• Several fixes for 64-bit ( Gerhard Tonn )
• fstat05,llseek fixes for MIPS ( Carsten Langgaard )
• - Fixed check in getgroups03 that was causing failures if 'nobody' isn't in any secondary groups ( Paul Larson )
• Fix sendfile02 to work with the new 2.5 kernels which no longer allow it to fall back on write ( Paul Larson )
• Changed the hard-coded ip address to 127.0.0.1 in recvfrom01-sctp-udp-ipv6 ( Robbie Williamson )
• Added instance and time command line options in runalltests.sh ( Jeff Martin )
• Fixed the algorithm description for fork07,fork12 Reduced the output of fork07 to a finite amount ( Nathan Straz )
• Added fork12 to runtest/crashme. ( Nathan Straz )
• Added option for interface selection in tcpdump01 ( Robbie Williamson )

CVS Bugs closed

#591695 getgroups03 fails on some distros
#591698 sendfile02 fails with 2.5 kernels

Acknowledgements

• Manoj Iyer,James Kenefick and Peter Oberparleiter for delivering the coverage analysis toolset.

Since Linus does not do pre-patches anymore, he mentioned some time ago it would be nice if somebody created an automated BK snapshot process to make BK changes accessible between kernel releases. I've done that.

ftp://ftp.kernel.org/pub/linux/kernel/people/jgarzik/snap/2.5/

All BK changes not in the current 2.5 kernel release will be posted at this URL, in GNU patch form, on a daily basis. [snap happens at one minute past midnight, California time] The full changelog log is also extracted. Each time Linus releases a new kernel, the contents of this directory will be wiped out.

Two more details:

• Just like a pre-patch, the Makefile EXTRAVERSION is hacked to indicate "-bk1", "-bk2", etc.
• I'll be setting up a process like this for 2.4, too, at the request of Marcelo

Heh, I've had something vaguely like this on NL.linux.org:

ftp://ftp.nl.linux.org/pub/linux/bk2patch/

Every 3 hours it creates a unidiff between the latest tagged version and the head of the bk tree, for both 2.5 and 2.4.

Just to forestall other private responses [already gotten two], mine is slightly different than your's, and David Woodhouse's setup. My goal was basically to create a daily pre-patch, complete with hacked EXTRAVERSION. That's something that is familiar to testers (pre-patch form), and the snapshot is not so often that people will get buried in a flurry of patches and csets. can you say "2.5.30-bk439" ;-)

So I consider my dailies as a complement to your bk2patch and dwmw2's output, not redundant. Programmers would probably find dwmw2's per-cset patches to be more useful, while testers and power users, and maybe maintainers, would prefer daily pre-patches to test and sync against.

Okay, I'm starting to have enough guts about this to release for testing...

klibc is a tiny C library subset intended to be integrated into the kernel source tree and being used for initramfs stuff. Thus, initramfs+rootfs can be used to move things that are currently in kernel space, such as ip autoconfiguration or nfsroot (in fact, mounting root in general) into user space.

I would particularly appreciate portability comments, since I'm flying blind on non-i386 machines (anyone want to send me hardware?), although any bug reports would be appreciated.

ftp://ftp.kernel.org/pub/linux/libs/klibc/klibc.tar.gz

I haven't bothered putting a version number on it, since it changes quite often. I have also published the CVS repository in the directory above.

You say that as if it were a bad thing.

(And technically incorrect, if you also provide .o files so that the end user can relink as they desire.)

That aside for the moment, isn't the plan to pull stuff that's currently GPL out of the kernel and link against this lib anyway?

Second point - if it goes into the kernel source tree as suggested, but with a 'copycenter' license, we can expect to have the nVidia problem but worse.

Making it GPL shouldn't be a big deal. It is intended to be a small amount of code, after all. And I'd hate to get into a situation where people started shipping their magic 'make the hardware work' bits as closed replacements for the early boot code.

I have no problems with people choosing whatever license they prefer for their work and I have no problems with using GPL when I'm working on projects that are already under it, but it's not the license I would choose for my work in cases when I have a choice.

As for the "make the hardware work" code, there's nothing to stop people from doing that _NOW_. I'm not too fond of that, but as long as we are talking about userland code it

• will have to use normal system calls
• will not have to link against any particular library, no matter what we provide
• will be up to those who write it and those who decide to use it.

We are talking about libc. _Nothing_ in that code couldn't be reimplemented by any half-competent programmer. It's a textbook stuff. Those who don't like GPL would be trivially able to reimplement all these functions in their own code anyway. End of story. Whatever license is chosen, it won't prevent people from putting their code under any license they like.

There is a crucial difference from the situation with nVidia, Veritrash and the rest of let's-bugger-the-kernel team. _They_ want more than using syscalls from user mode - they want an access to guts of the kernel and that's a very different can of worms. And _that_ I have problems with. A lot. Especially when they expect us to abstain from changes of kernel internals that might break their junk and when they whine when such changes are done.

People do have a right to put their code under whatever license they like. Now, _I_ won't use the stuff I don't have a source for unless I have exceptionally good reason to believe that authors of that stuff are among the few percents of programmers who *can* find their arse without outside help. But that has nothing to do with licensing or any moral considerations and everything to the fact that I know what kind of crap most of the software is.

- Fix small typo introduced in 113, which prevented CD-ROMs from working altogether.

- Eliminate block_ioctl(). This code can't be shared in the way proposed by this file. We will port it to the proper blk_insert_request() soon. This will eliminate the _elv_add_request() "layering violation".

- Don't play IRQ wreck havoc in ata_dump().

- Fix delays on seeks in ide-cd.c

- Integrate special_intr() and tcq_nop_intr() in to one single IRQ handler. This way we don't have to kmalloc anything for sending a NOP to the drive in TCQ.

- Eliminate the usage of the XXX_handler from the ata_taskfile structure. Now we always deduce which handler will be needed from the command which will be executed. This makes the usage of the channel IRQ handler pointer much more cleaner now.

- Don't pass taskfiles through rq->special. Pass them through rq->cmd[] as every other block device does or at least should do. This way we don't pass pointers to structures on local stack around any more.

- pdc4030 code doesn't have anything to do with the normal taskfile stuff.

I have confirmed by email with Jens (cc'ed to Martin) that Jens did not mean that Martin should step down as IDE maintainer or anything like that.

Jens was referring to the generic block code that he maintains (including elv_add_request and drivers/block/block_ioctl.c, which Martin had submitted patch for in IDE 115 without consulting with Jens).

Personally, I hope that Martin stays on as IDE maintainer. Getting IDE to a maintainable state was a minefield that had to be crossed. Could someone else have done with fewer mistakes? Maybe, but there was plenty of time for someone else to do it, and nobody stepped up to the plate. Of course there is a trade-off point that point is more conservatively set with the software that controls disk storage, but, in general, I think it's important to be supportive of those who actually produce.

So, you are new to Linux kernel hacking and want to submit a kernel bug report or a patch but don't know how to do it and _where_ to report it? Then save this file for future reference.

Preparing bug report:

Compile problems: report GCC output and result of "grep '^CONFIG_' .config" Oops: decode it with ksymoops Unkillable process: Alt-SysRq-T and ksymoops relevant part Yes it means you should have ksymoops installed and tested, which is easy to get wrong. I've done that too often.

More info in the FAQ at http://www.tux.org/lkml/

Sending bug report/patch:

• Some device drivers have active developers, try to contact them first.
• Otherwise find a subsystem maintainer to which your report pertains and send report to his address.
• Small fixes and device driver updates are best directed to subsystem maintainers and "small bits" integrators.
• It never hurts to CC: Linux kernel mailing list, but without specific maintainer address in To: field there is high probability that your patch won't be noticed. You have been warned.
• Do not send it to all addresses at once! This will annoy lots of people and isn't useful at all. It's a spam.
• Do NOT send small fixes to Linus, he just can't handle _everything_. He will eventually receive it from maintainers/integrators, send it their way.
• If your patch is something big and new, announce it on lkml and try to attract testers. After it has been tested and discussed, you can expect Linus to consider inclusion in mainline.

Current Linux kernel people

Note that this list is sorted in reversed date order, most recent entries first. This means than entries at bottom can be outdated :-(

Linux kernel mailing list <linux-kernel@vger.kernel.org>
        Post anything related to Linux kernel here, but nothing else :-)

Ingo Molnar <mingo@elte.hu> [30 jul 2002]
        Ingo wrote the new scheduler for 2.5.

Ralf Baechle <ralf@uni-koblenz.de> [30 jul 2002]
        I am maintainer of the AX.25 code

Victor Yodaiken <yodaiken@fsmlabs.com> [30 jul 2002]
        RTLinux patches, updates, contributions, drivers.
        Please send first to the list: rtl@rtlinux.org

Pavel Machek <pavel@ucw.cz> [27 jul 2002]
        I am network block device maintainer. Visit http://nbd.sf.net.
        (see Steven Whitehouse <steve@gw.chygwyn.com> entry)
        I am working on software suspend.

William Irwin <wli@holomorphy.com> [02 jul 2002]
        Send bug reports and/or feature requests related to many tasks,
        rmap, space consumption, or allocators to me. I'm involved in
        * rmap
        * memory allocators
        * reducing space consumed by data structures (e.g. struct page)
        * issues arising in workloads with many tasks
        * kernel janitoring
        See also:
        Rik van Riel <riel@surriel.com>
        Andrea Arcangeli <andrea@suse.de>
        Martin Bligh <Martin.Bligh@us.ibm.com>
        Andrew Morton <akpm@zip.com.au>

Dave Jones <davej@suse.de> [23 apr 2002]
        I collect various bits and pieces for inclusion in 2.5,
        especially small and trivial ones and driver updates.
        I'll feed them to Linus when (and if) they
        are proved to be worthy.

Andre Hedrick <andre@linux-ide.org> [09 apr 2002]
        ATA/ATAPI Storage Architect [2.0,2.2,2.4]
        HBA interface developer
        Serial ATA Architect [future release]
        Voting NCITS member AT-Attachment Committee

Andrea Arcangeli <andrea@suse.de> [28 mar 2002]
        Send VM related bug reports and patches to me.
        I'm especially interested in VM issues with:
        * lots of RAM and CPUs
        * NUMA
        * heavy swap scenarios
        * performance of I/O intensive workloads (in particular
          with lots of async buffer flushing involved)
        See also Martin J. Bligh <Martin.Bligh@us.ibm.com> entry
        Mail also:
        Arjan van de Ven <arjanv@redhat.com>

Martin J. Bligh <Martin.Bligh@us.ibm.com> [28 mar 2002]
        I'm interested in VM issues with lots (>4G for i386)
        of RAM, lots of CPUs, NUMA

Steven Whitehouse <steve@chygwyn.com> [27 mar 2002]
        I am the Linux DECnet network stack maintainer
        Visit http://www.chygwyn.com/decnet/

Arnaldo Carvalho de Melo <acme@conectiva.com.br> [26 mar 2002]
        IPX, 802.2 LLC, NetBEUI, http://kerneljanitors.org,
        cyclom2x sync card driver

John Cagle <jcagle@kernel.org> [19 mar 2002]
        The current maintainer of devices.txt, the list of
        assigned device numbers for LANANA.  Consult the web
        site (www.lanana.org) for instructions on submitting
        requests for new device numbers.  Send all device
        related email to <device@lanana.org>.

Tigran Aivazian <tigran@veritas.com>
        I am author and maintainer of BFS filesystem and IA32
        microcode update driver.

Rogier Wolff <R.E.Wolff@BitWizard.nl> [12 mar 2002]
        I do "specialix serial ports":
        drivers/char/specialix.c (IO8+)
        drivers/char/sx.c        (SX, SI, SIO)
        drivers/char/rio/*.c     (RIO)

Martin Dalecki <martin@dalecki.de> [11 mar 2002]
        IDE subsystem maintainer for 2.5
        (mail Vojtech Pavlik <vojtech@suse.cz> too)

Ed Vance <serial24@macrolink.com> [05 mar 2002]
        Maintainer for the generic serial driver, serial.c,
        for 2.2 and 2.4 kernels.  Please post patches to
        linux-serial@vger.kernel.org for tested bug
        fixes or to add support for a new serial device.
        Limited to time available. If I have not responded
        in a week, yell at serial24@macrolink.com

netfilter/iptables development <netfilter-devel@lists.samba.org> [23 feb 2002]
        Please report all netfilter/iptables related problems
        to this mailinglist, where all netfilter developers are present.
        See also http://www.netfilter.org/contact.html

Hans Reiser <reiser@namesys.com> [16 feb 2002]
        Send me all reiserfs related patches with a cc to
        reiserfs-dev@namesys.com, send bug reports to
        reiserfs-dev@namesys.com, send paid support requests to
        support@namesys.com after going to www.namesys.com/support.html
        to pay, send discussions (not bug reports unless they are
        interesting to most persons) to reiserfs-list@namesys.com.
        If we sit on your patch for a week without responding,
        yell at us, we deserve it.  Look at our web page
        at www.namesys.com for more about sending us code,
        working with us, and our patch submission and tracking system.

Paul Bristow <paul@paulbristow.net> [16 feb 2002]
        I am an ide-floppy driver maintainer
        (ATAPI ZIP, LS-120/240 Superdisk, Clik! drives).

Mike Phillips <phillim2@comcast.net> [15 feb 2002]
        Token ring subsystem and drivers.

Anton Altaparmakov <aia21@cam.ac.uk> [15 feb 2002]
        I am the NTFS guy.

https://bugzilla.redhat.com/bugzilla [14 feb 2002]
        Reports of problems with the Red Hat shipped kernels.

Alan Cox <alan@lxorguk.ukuu.org.uk> [14 feb 2002]
        Linux 2.2 maintainer (maintenance fixes only).
        Collator of patches for unmaintained things in 2.2/2.4.
        Maintainer of the 2.4-ac (2.4 plus stuff being tested) tree.
        I2O, sound, 3c501 maintainer for 2.2/2.4.

Robert Love <rml@tech9.net> [14 feb 2002]
        Preemptible kernel is mine.

ALSA development <alsa-devel@alsa-project.org> [12 feb 2002]
Jaroslav Kysela <perex@perex.cz> [12 feb 2002]
        Advanced Linux Sound Architecture
        ALSA patches are available at
        ftp://ftp.alsa-project.org/pub/kernel-patches/*

Neil Brown <neilb@cse.unsw.edu.au> [08 feb 2002]
        I am interested in any issues with the code in:
        NFS server    (fs/nfsd/*)
        software RAID (drivers/md/{md,raid,linear}*)
        or related include files.

Maksim Krasnyanskiy <maxk@qualcomm.com> [08 feb 2002]
        I'm author and maintainer of the Bluetooth subsystem
        and Universal TUN/TAP device driver.
        These days mostly working on Bluetooth stuff.

Rik van Riel <riel@conectiva.com.br> [07 feb 2002]
        Send me VM related stuff, please CC to linux-mm@kvack.org

Geert Uytterhoeven <geert@linux-m68k.org> [07 feb 2002]
        I work on the frame buffer subsystem, the m68k port (Amiga part),
        and the PPC port (CHRP LongTrail part).
        Unfortunately I barely have spare time to really work on these
        things. My job is not Linux-related (so far :-). I can not
        promise anything about my maintainership performance.

H. Peter Anvin <hpa@zytor.com> [07 feb 2002]
        i386 boot and feature code, i386 boot protocol, autofs3,
        compressed iso9660 (but I'll accept all iso9660-related
        changes.)  kernel.org site manager; please contact me
        for sponsorship-related issues.

kernel.org admins <ftpadmin@kernel.org> [07 feb 2002]
        Kernel.org sysadmins.  Contact us if you notice something breaks,
        or if you want a change make sure you give us at least 1-2 weeks.
        Please note that we got a lot of feature requests, a lot of
        which conflict or simply aren't practical; we don't have time to
        respond to all requests.

Greg KH <greg@kroah.com> [07 feb 2002]
        I am USB and PCI Hotplug maintainer.

Trond Myklebust <trond.myklebust@fys.uio.no> [07 feb 2002]
        I am NFS client maintainer.

James Simmons <jsimmons@transvirtual.com> [07 feb 2002]
        Console and framebuffer sybsustems.
        I also play around with the input layer.

Richard Gooch <rgooch@atnf.csiro.au> [07 feb 2002]
        I maintain devfs. I want people to Cc: me when reporting devfs
        problems, since I don't read all messages on linux-kernel.
        Send devfs related patches to me directly, rather than
        bypassing me and sending to Linus/Marcelo/Alan/Dave etc.

Russell King <rmk@arm.linux.org.uk> [06 feb 2002]
        ARM architecture maintainer.  Please send all ARM patches through
        the patch system at http://www.arm.linux.org.uk/developer/patches/
        New serial drivers maintainer for 2.5.  Submit patches to
        rmk+serial@arm.linux.org.uk

Andrew Morton <akpm@zip.com.au> [05 feb 2002]
        I'm receptive to any reproducible bug anywhere in the 2.4 kernel.
        Specialising in ext2, ext3 and network drivers.
        Not thinking about 2.5.x at this time.

Petr Vandrovec <vandrove@vc.cvut.cz> [05 feb 2002]
        ncpfs filesystem, matrox framebuffer driver, problems related
        to VMware - in all of 2.2.x, 2.4.x and 2.5.x.

Reiserfs developers list <reiserfs-dev@namesys.com> [05 feb 2002]
        Send all reiserfs-related stuff here including but not limited to bug
        reports, fixes, suggestions.

Oleg Drokin <green@linuxhacker.ru> [05 feb 2002]
        SA11x0 USB-ethernet and SA11x0 watchdog are mine.

Vojtech Pavlik <vojtech@ucw.cz> [05 feb 2002]
        Feel free to send me bug reports and patches to input device drivers
        (drivers/input/*, drivers/char/joystick/*)
        I also want to receive bug reports and patches for following
        USB drivers: printer, acm, catc, hid*, usbmouse, usbkbd, wacom.
        All other (not in the list) USB driver changes should go to USB
        maintainer (hopefully there is one listed here :-).
        Also CC me if you are posting VIA IDE driver related message
        (although I am not IDE subsystem maintainer).

======= These entries are suggested by lkml folks ========

Ralf Baechle <ralf@gnu.org> [27 mar 2002]
        I am mips/mips64 maintainer.

David S. Miller <davem@redhat.com> [07 feb 2002]
        I am Sparc64 and networking core maintainer.

======= These ones I made myself ========
======= I am waiting confirmation/correction from these people ========

Urban Widmark <urban@teststation.com> [13 feb 2002]
        smbfs

Jeff Garzik <jgarzik@mandrakesoft.com> [12 feb 2002]
        I am the network-card-drivers guy (8139 for instance).
        CC me and Andrew Morton <akpm@zip.com.au> on network driver patches.

video4linux list <video4linux-list@redhat.com> [12 feb 2002]
Gerd Knorr <kraxel@bytesex.org> [12 feb 2002]
        video4linux

Tim Waugh <twaugh@redhat.com> [08 feb 2002]
        > Who is maintaining the linux iomega stuff?
        For 2.4.x, me (in theory). I don't have time for 2.5.x at the moment.

Alexander Viro <viro@math.psu.edu> [5 feb 2002]
        I am NOT a fs subsystem maintainer. But I won't kill
        you if you send me some generic fs bug reports and (hopefully) patches.

Eric S. Raymond <esr@thyrsus.com> [5 feb 2002]
        Send kernel configuration bug reports and suggestions to me.
        Also I'll be more than happy to accept help enties for kernel config
        options (Configure.help).

G?rard Roudier <groudier@free.fr> [5 feb 2002]
        I am SCSI guy.

Jens Axboe <axboe@suse.de> [5 feb 2002]
        I am block device subsystem maintainer.

Keith Owens <kaos@ocs.com.au> [5 feb 2002]
        ksymoops, kbuild, .. .. .. .. .  are mine.

Linus Torvalds <torvalds@transmeta.com> [5 feb 2002]
        Do not send anything to me unless it is for 2.5, well tested,
        discussed on lkml and is used by significant number of people.
        In general it is a bad idea to send me small fixes and driver
        updates, send them to subsystem maintainers and/or
        "small stuff" integrator (currently Dave Jones <davej@suse.de>,
        see his entry). Sorry, I can't do everything.

Marcelo Tosatti <marcelo@conectiva.com.br> [5 feb 2002]
        Do not send anything to me unless it is for 2.4 and well tested.
        If you are sending me small fixes and driver updates, send
        a copy to subsystem maintainers and/or "small stuff" integrators:
        - Alan Cox <alan@lxorguk.ukuu.org.uk>,
        - Rusty Russell <trivial@rustcorp.com.au>.

Rusty Russell <rusty@rustcorp.com.au> [5 feb 2002]
        > Here are some cleanups of whitespace in .....
        Want me to add this to the trivial patch collection for tracking?
        If so just send (or cc:) it to trivial@rustcorp.com.au.

The block allocator code is one of the key remaining pieces we would have fixed before 2.4 shipped if we had had time. The block allocator code that shipped is simply ugly.

The block allocation algorithms in ReiserFS were once extremely simple. They would attempt to allocate a block near to its left neighbor in the tree ordering, searching for a free block starting from the block number of that neighbor, and doing the search in increasing block number order. (Increasing not decreasing block number order was significant to performance we found.)

The problem with this algorithm occurred when there were no free blocks anywhere near that neighbor. It would perform a linear scan of the bitmaps, and this scan might consume quite a lot of CPU as it checked each bit. Additionally, if you cannot get a free block near the neighbor, then proximity to the neighbor is actually a bad thing to achieve, because it means proximity to a full part of the disk.

So long ago I suggested that we try attaching a count to the bitmap, and not bother to scan its bits if that count was not zero. This new code does that.

Additionally, Jeff Mahoney wrote code to pick a random bitmap to go to if the current bitmap was full, and to try to make it a bitmap that is less than 90% full. This new code does that by default. (Oleg rewrote Jeff's code, and I have lost track of what aspects of it are Jeff's vs. Oleg's.)

However, we also tried a whole bunch of other things, and it looks like Jeff's/Oleg's code makes those other things not so valuable because those other things were achieving value by doing what Jeff's/Oleg's code does but less thoroughly or even as an unintended side effect.

In 2.4 we have code that takes all of the formatted nodes, and tries to put them into the first 10% of the disk. This makes me uncomfortable, because the 10% number is inflexible. Maybe I am wrong to dislike this. More experiments are needed, though I may wait for V4.1 to do them. It also does things with displacing things according to a hash function, which was a broken hash function at one time (you could tell that it didn't work the way that the programmer intended, and that it put things near to the start of the disk by accident due to directory ids tending to be numerically smaller than the device size in block numbers). I can't remember if that hash function has been fixed in the 2.4.19 code tree or if it is only fixed in our new patch.

We experimented with dispersing directories randomly across this disk.

We experimented with randomly displacing files large enough to have unformatted nodes (option in new allocator allows you to displace files larger than some arbitrary size).

In the end I decided that the improved bitmap scanning code plus the avoidance of 90% full bitmaps when nothing near is free plus starting from the left neighbor was close to as good as any other combination, and had the advantage of being simpler, so I made it the default, because I trust more in the robustness of simpler algorithms that I understand more fully.

The default code path is either far simpler than the current code, or clearly superior, depending on what part of it one considers. I do not claim that I have found the right answer, but I have probably found the best that I will invent for V3.

Almost everything that we at Namesys are going to change in V3 is written and going into the next several 2.4.20-pre* releases. The only thing that I know of that remains and is unwritten is to perhaps revert to the tail conversion policy used in Linux 2.2.* (the current code is very inefficient in its tail handling, and one of us thinks it might speed up if we go back to the old way, and I'd be interested to see a benchmark of it.) We would probably like to also junk the 4k at a time read code, but most likely that will be done in V4 (Linux 2.5/2.6) not V3.

V3 will probably change very little after 2.4.20, and that is what our users need in the period while V4 stabilizes --- they need something that always just works albeit not as fast as V4.

This patch implements the core framework for Multimedia Cards (MMC). It has been tested with iPAQ H3800 handhelds with MMC storage cards.

At the moment, access to the information required to write a driver for SD or SDIO requires signing and NDA that precludes the release of an open source driver, so only MMC is supported at this time.

Here's a patch against 2.5.30 that is the start of converting the USB code over to using the new core "struct device_driver" logic and functionality. Right now only the HUB and HID drivers are converted, and so they are the only ones that will work properly (the others will compile, but no devices are ever bound to them.)

The code is still quite rough in places, but the baic functions seem to work well (driver callbacks, etc.) There is some odd USB specific tweaks that were needed to be done in order to get this working properly.

The USB subsystem only binds drivers to USB "interfaces". A USB device may have many "interfaces", so a single device may have many drivers attached to it, handling different portions of it (think of a USB speaker, which has a audio driver for the audio stream, and a HID driver for the speaker buttons.) Because of this I had to create a "empty" device driver that I attach to the USB device structure. This ensures it shows up properly in the driverfs tree, and that no USB drivers try to bind to it.

Also, the driverfs representation of the USB devices has changed, possibly for the worse. Just try the patch to see what I mean :)

There is a known bug that happens in put_device() when a USB device is removed from the system, but the proper person already knows about it.

Comments?

If I don't hear any objections, I'll work on converting all of the USB drivers over to this model (the probe and disconnect function parameters have changed) and send the patch to Linus.

Many thanks to Pat Mochel for the original version of this patch (way back against 2.5.15) and for putting up with all of the USB device / interface madness.

This patch against 2.5.31 fixes some problems in the konicawc driver

• add new video mode 160x120
• add konicawc_camera_on/off()
• initially send out URBs in status,data order
• fix konicawc_isoc_irq to always resubmit status then data URBs
• tidy up debug messages
• make konicawc_compress_iso look for frame start on initial image

2.4 IDE was (re)written on top of the old ide code by Andre Hendrik. Seems that Andre, who it seems does really understand IDE and its quirks, can be a pain to work with... In early 2.5.x Linus started taking patches from Marcin (or Martin) Dalecki. Since then, with over a 115 patches, Marcin has proceeded to rewrite the IDE code. This has tended to make IDE a bit unstable in 2.5. About 2.5.26ish Jens Axobe got tired of the 2.5 ide problems and ported 2.4 ide to 2.5. This change was picked up in the Dave Jones series of kernels - it allows other pieces of the kernel to be tested while Marcin works towards a cleaner IDE.

IDE 2.5 is stable for some but not for others (like me) depending on it is iffy - have backups. If you do not want to test 2.5 IDE use -dj (Dave is a bit behind Linus now due to other work and a much needed vacation)

• sync up with (2.5.18?) pte/pfn/page/tlb etc. macros;
• asm-generic/tlb.h: loading unsigned long constant to unsigned int tlb->nr causes compiler warnings on 64 bit platforms.
• send_ipi_message() fix from Jeff Wiedemeier: The 2.5.30 IPI algorithm (with the to_whom == set test) incorrectly sends IPI messages to CPU 0 in a SMP system running with one processor. In this case to_whom is often 0 (cpu_present_mask & ~1UL << smp_processor_id()) which ends up triggering the to_whom == set case.
• migration IPI removed;
• Hardware cpu_id to logical cpu mapping is gone. Converted to cpu_online() etc.
• Historically, assembly routines included libc header <alpha/regdef.h> for OSF/1 register names. With the new kernel build system it doesn't work anymore. Make our own copy in <include/asm>.
• From Jay Estabrook: CIA rev 1 can't use DAC and windows 1,2 for SG.
• cli, sti an so on go away;
• irq_smp.c goes to /dev/null; the only leftover (synchronize_irq) moved to irq.c;
• hardirq count field in the preemption counter extended to 12 bits - one more than required for wildfire.
• Generic per-cpu areas; wrappers for SMP boot process.
• osf_getrusage() updated for new utime/stime fields of the task_struct;
• compatibility wrappers for OSF/1 v4 readv/writev syscalls: forward port from 2.4.19.
• pcibios_init() must be int;
• fls() - ctlz on ev67, generic on others. This was required for something several kernel releases back, now it seems to be unused. Anyway, it shouldn't hurt, so included here.
• missing #includes, missing #if RTC_IRQ in drivers/char/rtc.c;
• define USER_HZ;
• From Jeff Wiedemeier: rename alpha-specific config section 'General setup' to 'System setup' to avoid confusion with generic 'General setup';
• From Jeff Wiedemeier: fix the 'bootpfile' build.
• __down_[read,write]_trylock, __downgrade_write implemented;
• __builtin_expect replaced with unlikely().

Hmm. I've switched home machines this week, and people have been reasonably busy, so there is most likely a lot of dropped stuff.

There's a lot of merged stuff too, including various architectures getting up to speed with all the big changes (tlb and irq etc, and rmk is apparently trying to shrink his arm patch). Sparc64, alpha, ppc32, ARM..

The series of patches from Al Viro should fix a semaphore deadlock when partition reading was triggered while a new device was opened, and lay the groundwork for more disk description cleanups.

NTFS, JFS, driverfs and networking updates. USB, ISDN and network driver updates, partial merge with akpm (you've seen the discussions about some of the stuff dropped) etc. And let's see how much fallout there is from the 30-bit pids etc.

I have put the latest uClinux (MMU-less) patches at:

http://www.uclinux.org/pub/uClinux/uClinux-2.5.x/linux-2.5.31uc0.patch.gz

Nothing much new, just updated against 2.5.31.

Project page: http://www.csn.ul.ie/~mel/projects/vmregress/
Download: http://www.csn.ul.ie/~mel/projects/vmregress/vmregress-0.4.tar.gz

This is the first public release of VM Regress v0.4 (BumbleBee). It is the beginnings of a regression, benchmarking and test tool for the Linux VM. The web page has an introduction and the project itself has quiet comprehensive documentation and commentary so I am not going to go into heavy detail here.

There appears to be frequent trouble reliably testing the VM and comparing the impact (beneficial or otherwise) of VM features. As best as I can tell, there is heavy reliance on stress testing or intuitive decisions made by individual kernel developers to prove a VM is working or that is is better than another implementation. This tool eventually will be able to provide empirical data on VM performance as well as acting as a regression tool to make sure changes don't break anything.

It works by using kernel modules to get a definite view of what the kernel is at and to provide reliable, reproducible tests. Modules are divided up into 4 catagories. Core modules provide infrastructure for the tool. Sense modules tell what is going on in the VM. Test tests particular features and bench modules (none yet) will benchmark different sections of the VM.

The aim is to eventually eliminate guesswork in development. The tool will be able to tell for definite if a feature works. If it does work, it will be able to tell how well or poorly the feature performed. This will hopefully replace ad-hoc shell script tests and provide concrete performance data any developer can reliably produce and use as proof of "Feature X is better"

The interface to the tests are via proc at /proc/vmregress. Help is provided for most of them by cat'ing the entries after module load. The README and manual are very comprehensive and each c file has a detailed description at the top so I'm not going to go into heavy detail in this mail. The README includes a sample set of tests to illustrate how the tool can be used to provide useful information about performance.

This was developed against 2.4.18 and 2.4.19 but will compile with 2.5.30 and takes into account the existence of rmap (will compile and work with or without rmap). Bear in mind the tool is far for complete and I'm just looking for feedback on the viability and usefulness (or the lack thereof) of this tool. Consequently, it doesn't do much. Currently it

• Provides infrastructure such as proc helper functions, page table walk functions and so on
• Provides tests for the /proc interface to ensure it works
• Prints out the sizeof() VM related structs and prints out the memory usage
• Prints out information on all zones in the system
• Tests physical page allocation/free functions with either GFP_ATOMIC or GFP_KERNEL flags
• Tests page faulting routines

This has been tested heavily with UML 2.4.18 and with a dual PII350 running 2.4.19 . It is known to compile with 2.5.30 but I haven't done any 2.5 testing yet due to the lack of a crash box. It will work with or without rmap as the tool was written with it (as well as every other VM feature) in mind.

This sounds more like a micro benchmark tool, which is a good start, but the real problem with VM optimizations is, that they have to take into account real world load and especially user experience.

A simple example is the fact, that an idle desktop box will feel very sluggy if a user comes back after a few hours break, because all visible programs are paged out. To improve this, one could think about adding a flag to applications like "connected to gui". This feature would need a test then, which is no usual micro benchmark.

So I think it is a good idea to avoid to introduce slow operations in hot code path, but it does not help much the developers in the problem of simulating workload and measuring the interactive and real throughput.

But perhaps you can take this into account?

I am more interested in answering questions like

• Does subsystem X still work after changes made to it?
• How well does subsystem X perform?
• How long does it take to find pages to swap out?
• How much overhead is introduced by feature Y?
• What does my process space look like after vmscan does it's work?

For example, in time, it'll be able to tell exactly how well rmap is performing and compare it to a VM without rmap in terms of "how long it took to find a page to replace" and "what did the address space look like after kswapd worked". I should be able to show that rmap kept the correct pages in memory for instance where as an overall benchmarking tool is going to tell me nothing new. Used in combination with a profiling tool like oprofile, I should be able to get very specific performance data that I suspect will be useful to developers and to a much lesser extent, users.

I am making a persumption that if it can be shown that each individual component is working and performs well, then overall performance should improve.

We get too hung up on 'real world' world loads, that is not a productive way VM developers to spend their time. Developers need to use tests that focus on very specific aspects of VM performance. Yes, this testing should be backed up by 'real world' tests to confirm what the VM developer thinks, that improved performance on a subsystem translates into improved overall performance, and to keep a watch out for unexpected or undesirable interactions. That's called a 'reality tests'.

If you want to help with 'interactive performance', i.e., user experience, then *quantify what contributes to that* and write a micro-measurement tool that measures such things. E.g, latency of response to keyboard events under load. It's not rocket science, it just takes time and effort to set this kind of thing up so it's accurate and predictive.

It's an incredible waste of developer's time to be running 'reality tests' all the time, and never using more precise measurement methods. Anyone who wants to run reality tests and post the results is more than welcome to, and this is valuable. It's not valuable to throw mud at a testing/measurement tool because you think it's not 'realistic'.

The thing is that developers need some benchmarking thing they can script to run overnight. Watching vmstat for hours on end is not a useful way of spending development time.

On the other hand, if somebody could code up some scriptable benchmarks that approximate real workloads better than the current benchmarks do, I'd certainly appreciate it.

For web serving, for example, I wouldn't mind a benchmark that:

1. simulates a number of users, that:
1. load a page with 10 to 20 associated images
2. sleep for a random time between 3 and 60 seconds, "reading the page"
3. follow a link and grab another page with N images
2. varies the number of users from 1 to N
3. measures
1. the server's response time until it starts answering the request
2. the time it takes to download each full page

Then we can plot both kinds of response time against the number of users and we have an idea of the web serving performance of a particular system ... without focussing on, or even measuring, the unrealistic "servers N pages per minute" number.

In VM Regress land, I would be much more likely to provide a benchmark that did something like the folllowing. (Remember that VM Regress aims to provide more than been a pure benchmarking tool. Benchmarking is just one aspect)

1. Memory map with MAP_SHARED a number of regions
1. Each region is 512 pages large (2MB on a x86)
2. Create a number of regions until a percentage of memoryt is used that would hit the various watermarks of the zones
2. Over 1 hour do, reference regions with a gaussion pattern to simulate popular pages and images
3. At the end, give the best, worst and average time to read a region. Print out what regions are still resident in memory and compare that to the references. Regions referenced often should still be in memory and dead regions should be in swap
4. Repeat the test altering the following parameters
• The percentage of physical memory consumed to see what gets swapped out
• Simulate disk buffer usage instead of mmap'ing regions

With a low percentage of physical memory used, there shouldn't be anything too interesting happening because cache should be doing most of the work. With more regions, it should be noted how the VM holds up, how well it selects regions to swap out and how long it takes to find the proper pages and so on.

This type of benchmark is far away but I already do most of this work with the fault.o module. I memory map a region of which the size is related to the amount of physical memory (more accuratly it's related to the zone watermarks for the zone known to be affected by the test) and touch every page in the region. For n passes, I check if each page is present, if it's swapped out, I touch it to swap it back in. I then print out how many pages were swapped in, how many pages are physically present in the region and how long that pass took in milliseconds.

That is most of the work there so this isn't quiet vapourware, more a really dense fog. I just need a few more bits and pieces such as printing graphs of present pages vs references and meaningful data is easily accessible

I've been collecting trivial patches for a few months now, and it's time to solidify some rules:

1. Trivial patches must qualify for one of the following to be accepted:

   1. Spelling fixes (useful for grep, and sets a good example)
   2. Warning fixes (cluttering with useless warnings is bad)
   3. Compilation fixes (only if they are actually correct)
   4. Runtime fixes (only if they actually fix things)
   5. Removing use of deprecated functions/macros (eg. check_region).
   6. Contact detail and documentation fixes
   7. Non-portable code replaced by portable code (even in arch-specific, since people copy, as long as it's trivial)
   8. Any fix by the author/maintainer of the file. (ie. patch monkey in re-transmission mode)

   They must also be "trivial" by my definition of trivial. Best patches contain enough context for me to judge without opening the file (diff -C<nn> -u is your friend).

   NOTE: This means I'll only take whitespace/indentation fixes from the author or maintainer.

2. The patch will not be forwarded to anyone until a new kernel has been released after I receive the patch, *unless* noone else is sent the patch. So if you cc: the trivial patch monkey, it'll only be forwarded from there if it doesn't make the next kernel.
3. The first time the patch is forwarded, it will be sent to the author and/or maintainer. If they say they've included it in their tree, no more forwards will occur (modulo some timeout eventually). If they NAK it, the patch will be closed. Otherwise, the patch will be sent directly to Linus or Marcelo on future forwards (the maintainer will still be cc'd).

Hopefully this will be a good compromise between coordinating with maintainers who want control of their files, and stopping trivial patches from slipping through the cracks.

What happens in this case..

person a sends the monkey a patch.
person b replies to l-k (cc'ing monkey) with a "no do it this way" ?

do you have a hand-operated means to say "this patch supercedes the previous" ?

What would be *really* good, for the case where retransmits are necessary, if Alan hasn't picked it up for 2.4 (or me for 2.5), you could add us to the relevant Cc's, (and remove after Alan/Myself takes it).

This could however get tricky, as the same patch may need a bit of hand-merging to fit against -ac/-dj.

Maybe just simpler to remove us when Alan/I send an ACK ?

Release 1.0.21 of JFS was made available today.

Drop 59 on August 12, 2002 (jfs-2.4-1.0.21.tar.gz and jfsutils-1.0.21.tar.gz) includes fixes to the file system and utilities.

The new feature in this release is the capability to resize the file system.

Utilities changes

• add external log support to xpeek
• fix fsck.jfs to update log device number in superblock after logredo with external log.
• fix typo in mkfs.jfs Emergency help. (Bas)
• do not build currently unused defrag, extendfs utilities
• eliminate uuid redefinition compiler warnings
• add logsuper functions to libfs
• fix printf format specifiers. (Christoph Hellwig)
• code cleanup (all)
• update JFS FSIM for EVMS - see http://sourceforge.net/projects/evms/

File System changes

• define sb_bread for kernels older than 2.4.18
• C99-style initializers (Christoph Hellwig)
• Add resize function to JFS This is invoked by mount -oremount,resize=<blocks> See Documentation/filesystems/jfs.txt for more information.
• Remove d_delete calls from jfs_rmdir & jfs_unlink
• Dynamically allocate metapage structures Use slab cache and pool of reserved structures to manage the metapage structures. This is set up similar to the mempool routines in the 2.5 kernel. Previously a fixed number of these structures were preallocated. This did not scale well.
• Rework JFS's inode locking

For more details about JFS, please see the patch instructions or changelog.jfs files.

For the Nth time, here again is the patch for fixing the scheduler for correct SCHED_FIFO and SCHED_RR behaviour.

I waited to see it in 2.4.20-pre1, not there, 2.4.20-pre2, not there...

Please apply it in 2.4.20-pre3

QLogic is pleased to announce the 6.01b4 release of its qla2xxx driver for ISP2100/ISP22xx/ISP23xx chips and HBAs.

Major improvements from the 5.3x driver series include:

• Robust and stable failover implementation
• Fast-path cleanup
• Support for the new error-handling routines
• Report-luns scan
• ISP2342 support
• IP via FC support (RFC 2625)
• ISP2100 support.
• 64bit DMA addressing
• Remove virt_to_bus/kmalloc --> pci_* routines
• Memory mapped I/O support
• General code-sanitizing
• locking structures
• queue structures
• extraneous NOP *LOCK/UNLOCK macros
• remove old EH routines
• remove serial console routines

The 6.xx series driver supports kernels 2.4.x and above ONLY, and contains most of Arjan van de Ven's (Redhat) changes made to the 5.31 driver.

A side note regarding ISP2100 support: QLogic has formally retired the QLA2100 card and will *not* provide technical support for these chips and HBAs. The initial 6.xx series drivers were stripped of ISP2100 card recognition. The current ISP2100 support was forward-ported from 5.3x. From an engineering standpoint, any patches or fixes for the ISP2100 will be considered.

The driver distribution can be downloaded at:

http://download.qlogic.com/drivers/5537/qla2x00-v6.1b4-dist.tgz

The distribution contains three main components:

qla2x00src-vX.YY.tgz -- The FC/SCSI driver
qla2xipsrc-vM.NN.tgz -- The IP network driver
qlapi-P.QQ-rel.tgz -- The SNIA API library

Changes since 6.01b2 distribution:

QLA2X00:

• Remove qla_dbg.h and qla_def.h files from driver distribution.
• Remove all virt_to_* calls in both SCSI/IP driver sources.
• 64bit DMA addressing through dma_addr_t.
• Cleanup structure names/member variables from IP sources.
• Add QL_DEBUG_LEVEL_12 for IP debugging.
• Add transmission timeout callback for IP driver.
• Enable SRAM, Instruction RAM and GP RAM parity checks on ISP2300s.
• Display all luns recognized by driver in /proc, not just SCSI mid-layer scanned luns. Luns not scanned by the mid- layer are marked with an asterisk (*).
• Add FC_SUPPORT_RPT_LUNS flag to the struct fc_port.flags. Set, if the device supported the report luns command.
• Increase Inquiry request buffer to 36 rather than 4. Some target devices have problems with the small transfer.
• Fix assignment of current_speed during an asyncronous event MBA_LOOP_UP. Improper connection speed was being reported to EXIOCTs and IP driver.
• Add ISP2100 support:
• QLogic provides no support for the ISP2100.
• compiled binary name qla2100.o.
• Forward-port chip support from 5.[2|3]x series driver.
• Update Makefile.kernel and Config.in.
• add new 2100 TP firmware (1.19.24).
• Fix copy-error in qla2x00_fo_get_params() where the qla_fo_params notification CDB would be zero'd-out.
• Fix kernel-oops when DEBUG level 5 is enabled and a command is sent to a non-existent lun.
• Fix in-kernel compilation problem (Veritas).
• Remove superfluous KMALLOC*/KMFREE/BZERO/BCOPY/ BCMP/qla_bcopy defines and functions.
• Remove unused ql_list_link structures and functions.
• Consistent use of copy_to/from_user() functions (RH).
• Consistent use of scsi_qla_host_t instead of several aliases (RH).
• Remove illegal usage of caddr_t (RH).
• Remove Target-Mode support from driver.
• Cleanup qla_fo.c file:
• Remove old debugging code.
• General sanitizing.
• Cleanup compiler warnings during debug builds.
• Add new 2300 IP/TP firmware (3.01.13).

QLA2XIP:

• Requires v6.01b4 SCSI driver.
• Add completion status to send and receive control buffers.
• Add support for specifying the MTU (mtu) and Receive buffers count (buffers) on the modules command line.
• Add NETIF_F_HIGHDMA to the device feature flags if 64bit DMA addressing possible.
• Add tx_timeout() implementation.
• Add display of link connection speed during initialization.
• Fix race in qla2xip_free_send_cb().
• Remove all virt_to_* calls in driver sources.
• 64bit DMA addressing through dma_addr_t.
• Use system-defined structures for network/ethernet support.
• Use hton/ntoh functions.
• Cleanup structure names/member variables.

ftp://oss.sgi.com/projects/xfs/download/patches/2.4.19.

The xfs patches for 2.4.19 have been respun as of 2002-08-13 01:22 UTC. This includes kdb v2.3 2.4.19 common-2, i386-3 plus some recent quota and acl fixes.

For some time the XFS group have been producing split patches for XFS, separating the core XFS changes from additional patches such as kdb, xattr, acl, dmapi, kbuild 2.5. These patches were initially intended for internal use and for feeding to Linus but we got no response at all. The split patches are now being released to the world with the hope that developers and distributors will find them useful.

Read the README in each directory very carefully, the split patch format has changed over a few kernel releases. Any questions that are covered by the README will be ignored. There is even a 2.4.20/README for the terminally impatient :).

UML has been updated to 2.5.31 and UML 2.4.18-52.

The changes since 2.5.30 have been mostly bug fixes and cleanups.

I fixed a "I'm tracing myself and can't get out" race.

The kernel entry and exit code was cleaned up and reduced from three copies to one.

telnetd is now killed when UML shuts down, so telnet connections to UML consoles die properly.

Fixed a crash caused by a non-GFP_ATOMIC allocation in an interrupt.

UML now exits when 'debug' is asked for and CONFIG_PT_PROXY is disabled.

Fixed some bugs in the ubd device plugging code.

Fixed ethertap by making CLOEXEC optional in os_pipe.

Made UML build on 2.2 by defining the SHUT_* macros if no header file does.

The patch is available at
http://uml-pub.ists.dartmouth.edu/uml/uml-patch-2.5.31-1.bz2

For the other UML mirrors and other downloads, see
http://user-mode-linux.sourceforge.net/dl-sf.html

Other links of interest:

The UML project home page : http://user-mode-linux.sourceforge.net
The UML Community site : http://usermodelinux.org

The Linux Test Project test suite LTP-20020813 has been released. Visit our website ( http://ltp.sourceforge.net ) to download the latest version of the test suite.

There are some important fixes in this release, so please consider upgrading.

LTP-20020813

* Fixes

• Fix runtest/commands to export the correct TCdat ( Paul Larson )
• Add some missing includes and remove warnings about missing prototypes ( Andreas Jaeger )
• Add better initialization to waitpid05, signal04, getgroups01 ( Robbie Williamson )
• Fix sockioctl01 to work even if fd0 isn't open ( Paul Larson )
• Fix mmstress path problems, now uses execvp ( Paul Larson )

This is an announcement of a set of 38 patches against Linux 2.5.31, which implement basic NFSv4 functionality. The patches were developed as part of the NFSv4 project at the University of Michigan. We are aiming to work with other kernel developers in the next few weeks, to get the patches included in 2.5.x. In addition, we could always use more testing, so if anyone wants to apply the patches and bang on them, that would be extremely helpful as well.

For now, only the bare minimum of features have been implemented -- just enough to create a functional network file system. Byte-range file locking, state management, recovery from server reboot, extended attributes, ACL's, the NFSv4 "pseudo filesystem", and strong security are still unimplemented in 2.5.x. Actually, we have implementations of most of these features in 2.4.x, but are waiting to port them to 2.5.x until the "minimal" patches have been approved.

(For those familiar with the NFSv4 protocol, I should elaborate by saying that the client does all of its READs and WRITEs using "magic stateids" and uses OPEN and CLOSE only when it needs to create a file. The server treats all state-manipulating operations such as SETCLIENTID,OPEN,CLOSE... as no-ops and does not remember state. Instead of a proper implementation of the pseudo filesystem, the first entry in /etc/exports is chosen as the nominal root.)

Here are directions for running NFSv4. Note that a few userland utilities are necessary (URL's given as needed):

1. Apply the NFSv4 patches to a clean 2.5.31 kernel, either one at a time from the messages following this one, or all at once by downloading the "grand unified patch" from www.citi.umich.edu/projects/nfsv4/patches-2.5/patch-2.5.31-E. There will be seperate kernel config options for NFSv4 support in the client and server.
2. Download and install the GSSD daemon from www.citi.umich.edu/projects/nfsv4/simple-gssd/. This daemon must be running on both the client and server.

3. Warning!! Special configuration on the server is necessary before an NFSv4 export will be accessible.

   First, it must be exported specifically to the client in question, without use of string wildcards, e.g.

   /some/export farringdon.citi.umich.edu(rw)

   in /etc/exports is OK, but

   /some/export *.citi.umich.edu(rw)

   is not.

   Second, only the _first_ export (by order in /etc/exports) will be visible to a given client.

   Finally, this export will appear to an NFSv4 client as '/index.html' instead of the actual export pathname (/some/export in the example above).

   All of this special configuration is only necessary because this set of patches does not include a proper implementation of the NFSv4 pseudo filesystem. As soon as these patches patches (or a variant thereof) is incorporated into the kernel, our next goal is to develop a satisfactory pseudofs for 2.5.x, at which point the need for this special configuration will go away.

4. On the client, you will need a patched version of the mount and umount utilities. Download util-linux-2.11t from kernel.org, apply the patch

   www.citi.umich.edu/projects/nfsv4/patches-2.5/patch-util-linux-2.11t-A

   and build mount and umount as usual. If you are nervous about tampering with the built-in mount and umount on your system, we recommend creating symlinks, e.g.

   # ln -s /usr/src/util-linux-2.11t-nfsv4/mount/mount /usr/local/bin/mount4
   # ln -s /usr/src/util-linux-2.11t-nfsv4/mount/umount /usr/local/bin/umount4

   You should then be able to start the server as usual, and mount with

   # mount4 -t nfs -o vers=4,... somehost.somedomain.com:/ /mnt/nfs

   If this doesn't work, it is probably because GSSD is not running on either the client or the server, or because you're not mounting '/index.html' (see 3. above).

These directions, as well as copies of the patches, are also available at www.citi.umich.edu/projects/nfsv4/patches-2.5. This URL will always be kept up-to-date with the latest versions of the patches.