Hurd on a cluster computer

Hi - I've been wondering about using Hurd on a cluster computer; i.e, a configuration where each node has multiple identical cores and its own memory. For example, an eight node cluster where each node has 8 GB of RAM and eight cores. I stress that the cores are identical, so that processes can

Re: Fwd: Hurd shutdown problems

On Wed, Aug 10, 2016 at 4:33 AM, Richard Braun wrote: > On Wed, Aug 10, 2016 at 04:26:35PM +0200, Richard Braun wrote: > > the boot loader (see MULTIBOOT_FLAGS in boothdr.S), and at > > some point, late during the boot process, module data are freed > > using (see

Re: Fwd: Hurd shutdown problems

On Mon, Aug 8, 2016 at 9:32 PM, Justus Winter <jus...@gnupg.org> wrote: > Hello, > > "Brent W. Baccala" <cos...@freesoft.org> writes: > > > I don't have to swapoff to have "symptoms". The kernel debugger normally > > shows symbolic na

Re: [bug #48685] update-grub triggers filesystem server panics

On Tue, Aug 2, 2016 at 9:52 PM, Justus Winter wrote: > > The isofs crash is fixed in 21ee0e79. Please update your Hurd packages. > > The fact that you are seeing these messages is a (quite nice actually) > side-effect of 234568d0. I guess that if you were doing this on

Re: Fwd: Hurd shutdown problems

Aloha - I've updated to the latest Debian kernel package, which includes Samuel's patch. (thank you) This fixes the symbol table problem, but my VM still locks up after a failed swapoff. I do, however, get symbolic names displayed correctly from the kernel debugger at that point. Obviously,

Hurd shutdown problems

Aloha! Well, I think that I've resolved my boot hangs by removing the -no-kvm-irqchip flag, now I'm trying to resolve the occasional hang when the system shuts down. The filesystem always gets corrupted if the system can't cleanly halt, so it's a real problem. Here's some debugging info from

Fwd: Hurd shutdown problems

Further progress trying to track this down: I don't have to shutdown the system to have problems. "swapoff /dev/hd0s5" is enough to cause problems, once enough swap is in use. After a failed swapoff, I have an extra 98 storeio processes running! I don't have to swapoff to have "symptoms". The

Re: Hurd shutdown problems

On Sat, Aug 6, 2016 at 7:59 AM, Justus Winter wrote: > > To prevent filesystem damage, try the following. Break into the kernel > debugger, and kill the auth server using: > > !task_terminate($task5) > > Then continue using "c", and /hurd/startup should cleanly shutdown the >

[PATCH] Re: Hurd shutdown problems

Aloha - OK, I seem to have gotten a handle on this thing now. First, there's a missing mutex unlock in mach_defpager. I'm attaching two patches. One fixes the debug printfs in mach_defpager/default_pager.c, which obviously haven't been compiled for a while. Use %p and %lx instead of %x to

Re: netmsg

On Tue, Aug 23, 2016 at 2:12 AM, Richard Braun wrote: > > > It's got a lot of problems. No authentication handoff; everything the > > client requests happens with the permissions of the server. exec'ing a > > file doesn't work; the last RPC before the hang is

exec server behavior

Aloha - My recent experiments with 'netmsg' have lead me to investigate the operation of Hurd's exec server, and I've got a few questions. First off, the current obstacle to exec'ing files over netmsg is the need to operate the memory_object protocol over the TCP/IP connection. libpager has a

Re: netmsg

On Tue, Aug 23, 2016 at 11:45 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > > Any ideas why this basic sequence wouldn't work? > >node = file_name_lookup("/lib/ld.so", O_RDONLY, 0) >io_map(node, , ) >/* create control and objnam

problems with a subhurd

Aloha - While testing the exec server, I setup a very minimalist subhurd using just the most essential files, as opposed to copying the entire filesystem, and uncovered a number of bugs. I've refined the process into a shell script (attached) which creates the subhurd on a ramdisk and then boots

RFC: Revised authentication protocol

Aloha - For those of you who have followed my netmsg threads, you may remember that there were two major issues when I first got it running. One was libpager's lack of multi-client support, which has been discussed at length, and the other was authentication, which we haven't discussed at all.

firmlink deleting files on boot / interpretation of find -xdev switch

On Thu, Sep 1, 2016 at 12:38 PM, Richard Braun wrote: > This was famously shown with the example of the > firmlink translator used in /tmp, which would cause the removal of > any file targeted by the firmlink on /tmp cleanup during system > startup. > I see that. It seems to

Re: firmlink deleting files on boot / interpretation of find -xdev switch

On Tue, Sep 6, 2016 at 2:05 AM, Richard Braun <rbr...@sceen.net> wrote: > On Mon, Sep 05, 2016 at 09:55:44PM -1000, Brent W. Baccala wrote: > > I haven't been able to find any other places on my system where find uses > > -xdev; just bootclean.sh, but my search ha

Re: mach_msg blocking on call to vm_map

On Thu, Sep 1, 2016 at 10:28 AM, Richard Braun wrote: > > I completely disagree. Thank you, Richard. Really! Thank you for disagreeing. Now we can have a good discussion about this! > Most modern microkernels use synchronous IPC > that just block, and many operations on

mach_msg blocking on call to vm_map

Aloha - I've run into a real kernel-level problem with 'netmsg'. It's related to the libpager issue. The problem arises when a process gets an unworkable memory object and tries to vm_map it. This causes the mach_msg() that sent the vm_map to block indefinitely, even though I've specified

Re: mach_msg blocking on call to vm_map

On Thu, Sep 1, 2016 at 12:38 PM, Richard Braun wrote: > > > Most modern microkernels use synchronous IPC > > > that just block, and many operations on top of them do block. The > > > overall system on the other hand must be careful to avoid such > > > deadlocks. > > > > OK, I

Re: firmlink deleting files on boot / interpretation of find -xdev switch

On Wed, Sep 7, 2016 at 11:49 AM, Richard Braun wrote: > > We really, really don't want to make standard Unix tools aware of > Hurd-specific stuff, because that allows us to completely reuse the > work of others. With a trend towards systemd, it's even more likely > that our

Re: netmsg can now exec files (sort of)

I've figured out why the patched exec server didn't work with mmap, and just opened a bug on it, with a fix attached. So now I've got a working, mmap-less exec server that burns a lot of extra RAM (each process gets its own private copy of the C library), but lets me execute files across a netmsg

Re: Denial of service attack via libpager

On Sun, Aug 28, 2016 at 11:15 PM, Richard Braun <rbr...@sceen.net> wrote: > On Sun, Aug 28, 2016 at 05:12:35PM -1000, Brent W. Baccala wrote: > > > The obvious additional client would be a remote kernel, but as the > exploit > > program that I posted sho

Re: [PATCH gnumach] RFC: Create a malleable syscall interface.

On Thu, Sep 22, 2016 at 12:21 PM, Justus Winter wrote: > > % ~/build/machometer/machometer > N: 33554432 (1<<25), qlimit: 5 > mach_print: 5s75us171.363354ns5835553.391 (1/s) >nullmsg: 6s33us188.648701ns5300858.136 (1/s) > producer:

netmsg can now exec files (sort of)

Aloha - I've gotten 'netmsg' to the point where files in the mounted, remote filesystem can be executed on the local machine. This isn't remote execution - it's just copying the files to the local machine and executing them there. Nothing more than what you'd expect from NFS or Samba, but it

netmsg

Aloha - I've gotten a basic netmsg server/translator running that relays Mach messages across a TCP/IP connection. The code is available at g...@github.com:BrentBaccala/netmsg.git Basic usage: netmsg -s (server) settrans -a node netmsg localhost (client) It's got a lot of problems. No

Denial of service attack via libpager

Aloha - I've written a short program (attached) that demonstrates how libpager's support for only a single client can be used to mount a denial of service attack against the kernel. It works by opening a file, grabbing its associated memory object (if it can), and holding it until you hit

Re: Denial of service attack via libpager

On Sun, Aug 28, 2016 at 12:49 PM, Richard Braun wrote: > > I'm really not seeing the relation between "multiple clients" and > "multiple threads". Libpager must be able to handle multiple clients > with a single thread, otherwise we don't control scalability and we're > back to

Re: behavior of NO SENDERS notifications when receive rights move

On Fri, Sep 30, 2016 at 9:17 AM, Kalle Olavi Niemitalo wrote: > > A future version of rpctrace might want to move receive rights > if it were able to attach to a preexisting task. > That's an important and interesting application that I hadn't thought of. Now I'm wondering - how

Re: RFC: Revised authentication protocol

On Mon, Sep 19, 2016 at 9:52 AM, Olaf Buddenhagen wrote: > I'm a bit confused here: my understanding was that you essentially > wanted to implement a "single system instance" cluster. I would have > thought that would imply only a single instance of most servers -- >

Re: rpctrace design

On Mon, Oct 24, 2016 at 1:12 AM, Justus Winter <jus...@gnupg.org> wrote: > > "Brent W. Baccala" <cos...@freesoft.org> writes: > > I read on the website's hurd/debugging/rpctrace page that somebody > (zhenga) > > had come with a new version o

Mach "pipe" between parent and child

hi - What is the best way to fork() a child and have a Mach receive right on the parent connected to a send right on the child? Or vice versa? agape brent

Re: [PATCH 8/8] rpctrace: use condition variable to keep messages in sequence

On Oct 29, 2016 2:55 AM, "Samuel Thibault" wrote: > > Hello, > > Better apply this patch before patch7, shouldn't we? Otherwise there's > a little git interval during which rpctrace is unreliable. > > Samuel I had thought of the entire patch set being applied

Re: [PATCH 1/8] remove warning messages on rpctrace from 'asprintf'

On Oct 29, 2016 2:53 AM, "Samuel Thibault" wrote: > > Hello, > > > #define easprintf(args...)assert(asprintf (args) != -1) > > That will be removed when building with -DNDEBUG, not a good thing :) An excellent point. I'll revise PATCH 1 tomorrow. > Also, I

rpctrace / libpager / signal preemptor

Hi - Just a status update about what I'm working on. My primary goal right now is to get ext2fs working right when a ramdisk fills up. dd hangs and/or crashes ext2fs instead of cleanly erroring out. First, there's a problem in libpager --- a/libpager/data-unlock.c +++ b/libpager/data-unlock.c

gsync/libihash hash function

Hi - My recent foray into gsync left me thinking a bit about its hash function: #define MIX2_LL(x, y) x) << 5) | ((x) >> 27)) ^ (y)) which seems a bit weak. The result of gsync_key_hash is then taken modulo GSYNC_NBUCKETS, which is currently 512. libihash has a similar issue. It seems

Re: kernel panic in gsync_wait

On Fri, Nov 4, 2016 at 12:00 AM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Brent W. Baccala, on Thu 03 Nov 2016 15:51:04 -1000, wrote: > > I see... so there must be fallback code (option 2 on my list); I just > haven't > > found it. > > > > Where i

Re: libpager multi-client support

Aloha - I've been thinking more about the data structures involved with the new libpager code, and they're complex enough that I'd like to write them in C++11. The pagemap has to contain a list of all clients with copies of a page, and a queue of clients waiting to access the page. To keep the

commit 341f43d: boot: Ignore EINTR.

Dear Justus, What are the symptoms of this bug? I've been seeing sporadic behavior where my boot hangs right after "exec" prints in the "Hurd server bootstrap" line. Is this patch related to that? agape brent

rpctrace design

Aloha - I've been trying to debug a problem in rpctrace which causes rpctrace to crash when I use it to wrap /hurd/ext2fs. The bug is triggered by a memory_object_lock_request / memory_object_lock_completed sequence. Specifically, ext2fs sends a lock request to the kernel with a send-once

Re: libpager multi-client support

On Tue, Oct 18, 2016 at 2:37 AM, Richard Braun wrote: > > From my fifteen years or so experience working in various projects with > C++ and other languages, my opinion is that C++ is never the best > choice. It makes you trade lines of code for increased complexity in >

Re: gdb and PIE binaries

On Fri, Nov 11, 2016 at 7:17 AM, Samuel Thibault wrote: > Hello, > > Debian is pushing more and more PIE builds, so that address > randomization can be done. However, on GNU/Hurd, gdb can't work with > core files from processes running PIE programs, so one has to pass >

Re: C++ vs. glibc/Hurd/Mach headers

On Fri, Nov 25, 2016 at 1:46 AM, Thomas Schwinge wrote: > Hi! > > Motivation for bringing this up again: GDB has recently switched from > using a C to a C++ compiler. GDB, for obvious reasons, needs to access > low-level Hurd/Mach interfaces. > > I've also had problems

signal preemptors

Coming back to the subject of signal preemptors... Why do we need them at all? Why not just use the existing POSIX signal facilities? We install a signal handler, saving the old signal handler, check the faulting memory address inside the new signal handler, and relay the signal on to the saved

Re: gdb handling of Mach exceptions

On Wed, Nov 23, 2016 at 10:03 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > > Any comments? > Well, yes, actually. :-) gdb's hurd target has a poorly documented command "set noninvasive". I don't completely understand it, but... I'm starting to see the

Re: rpctrace / libpager / signal preemptor

On Sun, Nov 20, 2016 at 5:37 AM, Samuel Thibault wrote: > Samuel Thibault, on Sun 20 Nov 2016 14:50:50 +0100, wrote: > > Samuel Thibault, on Wed 16 Nov 2016 20:05:49 +0100, wrote: > > > Samuel Thibault, on Wed 16 Nov 2016 19:50:07 +0100, wrote: > > > > And is fixed by

gdb handling of Mach exceptions

Hi - I've been trying to use gdb on ext2fs when it runs out of disk space and starts generating memory access exceptions. It doesn't behave right. The memory faults get reported as unknown signals and the program can't be restarted: Program received signal ?, Unknown signal. [Switching to

Re: [PATCH 1/8] remove warning messages on rpctrace from 'asprintf'

On Sat, Oct 29, 2016 at 1:40 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > On Oct 29, 2016 2:53 AM, "Samuel Thibault" <samuel.thiba...@gnu.org> > wrote: > > > > Hello, > > > > > #define easprintf(args...)assert(asprintf (

Re: [PATCH 8/8] rpctrace: use condition variable to keep messages in sequence

On Sat, Oct 29, 2016 at 1:48 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > Yes, patch7 without patch8 can reorder messages as they're being resent, > but patch8 uses the mutex introduced in patch7, so the ordering can't be > reversed. > > They could be combined into a

rpctrace man page

Hmm... maybe somebody on the list will fix the gsync bug, since I don't know how... ...what can I do in the meantime... How about writing a man page? agape brent rpctrace.1 Description: Binary data

Re: two more rpctrace patches

On Wed, Nov 2, 2016 at 2:39 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > On Wed, Nov 2, 2016 at 2:26 PM, Kalle Olavi Niemitalo <k...@iki.fi> wrote: > >> >> Look at how the commit messages in hurd.git at Savannah (not at >> Debian) are formatted.

Re: kernel panic in gsync_wait

locking primitives directly, they're used by the C library, right? On Sun, Oct 30, 2016 at 10:16 PM, Kalle Olavi Niemitalo <k...@iki.fi> wrote: > "Brent W. Baccala" <cos...@freesoft.org> writes: > > > Even if I'm right about the nature of this bug, I don't un

minor bug in glibc

Hi - I'm using my newly enhanced rpctrace to hunt down a few bugs. Here's a minor one in glibc that shows up like this on "rpctrace /bin/true": task337(pid1240)->mach_port_deallocate (pn{ 0}) = 0xf ((os/kern) invalid name) The trick is to get rpctrace to halt the process when it encounters

kernel panic in gsync_wait

Hi - My new and improved rpctrace is generating kernel panics when run on ext2fs. This happens when rpctrace calls gsync_wait, with ext2fs as the 'task' argument. Could you guys look at gnumach's kern/gsync.c, at line 212? It looks to me like that code tacitly assumes that the 'addr' it's

Re: two more rpctrace patches

On Wed, Nov 2, 2016 at 3:10 AM, Justus Winter wrote: > > Cool. Two nitpicks: 1/ Instead of attaching patches, why don't you use > git send-email. That is easier for everyone. 2/ The summary line of > your patches is too long, try to keep it at ~60 chars or so, and we >

Re: two more rpctrace patches

On Wed, Nov 2, 2016 at 2:26 PM, Kalle Olavi Niemitalo wrote: > > Look at how the commit messages in hurd.git at Savannah (not at > Debian) are formatted. "make dist" runs gitlog-to-changelog, > which generates a ChangeLog file from those. > OK, I think I see what you want.

Re: kernel panic in gsync_wait

On Thu, Nov 3, 2016 at 2:18 PM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Brent W. Baccala, on Thu 03 Nov 2016 14:12:41 -1000, wrote: > > I suspect that this ultimately affects just about every program on a > > Hurd system. > > Sure, it's used internally by

rpctrace

Hi - I've made some decent progress with rpctrace this week. I think I pretty much understand this program now! In particular, I've gotten it working on ext2fs. I had to fix the problem I described earlier with send-once rights, and then deal with a deadlock situation caused when ext2fs called

Re: rpctrace man page

On Tue, Nov 1, 2016 at 5:15 AM, Samuel Thibault wrote: > > GNU projects usually don't have man pages, but info pages. The > doc/hurd.texi indeed doesn't have any part for rpctrace. It should :) > > What an embarrassing *faux pas*! It's like fumbling to put the Metro

two more rpctrace patches

Aloha - I'm attaching two more patches to rpctrace that close bug 48863. agape brent From 10a2a49e370ca55b6cea4cdc4a54ae106b243817 Mon Sep 17 00:00:00 2001 From: Brent Baccala Date: Tue, 1 Nov 2016 01:07:52 -1000 Subject: [PATCH 1/2] rpctrace: don't wrap send-once

libpager multi-client support

aloha - I've started looking at adding multi-client support to libpager. My first question is for advice on managing my workflow. I'm using the Debian hurd package, which adds patches on top of a snapshot taken from savannah's git tree. I think I want to work on the Debian-ized code, since

Re: workflow with Debian patches and Git repositories (was: libpager multi-client support)

On Sat, Oct 15, 2016 at 11:17 PM, Kalle Olavi Niemitalo wrote: > > I also have a "hurd-debian" working tree. I extracted that from > the Debian source package, so that I got a .pc directory with the > correct state information. I then added a .git directory cloned > from

Re: rpctrace / libpager / signal preemptor

On Wed, Nov 30, 2016 at 11:12 PM, Samuel Thibault wrote: > > Err, I'm sorry, did you perhaps miss the fix I made after: > > commit 406b031c996ec4cd8c76d251de8b7bf462d8b975 > Author: Samuel Thibault > Date: Sun Nov 20 16:16:24 2016 +0100 >

Re: rpctrace / libpager / signal preemptor

On Wed, Nov 16, 2016 at 9:05 AM, Samuel Thibault wrote: > Samuel Thibault, on Wed 16 Nov 2016 19:50:07 +0100, wrote: > > Samuel Thibault, on Wed 16 Nov 2016 19:46:52 +0100, wrote: > > > The attached testcase does get the faulting address. > > > > And the attached

Re: multi page memory object operations

On Mon, Jul 31, 2017 at 5:21 AM, Richard Braun <rbr...@sceen.net> wrote: > On Sun, Jul 30, 2017 at 10:20:55PM -0400, Brent W. Baccala wrote: > > > Does anybody know the history of multi page requests? Was it ever > > implemented in the kernel? > > Maksym Planeta wo

Re: libpager

On Sun, Aug 6, 2017 at 2:34 PM, Justus Winter <jus...@gnupg.org> wrote: > "Brent W. Baccala" <cos...@freesoft.org> writes: > > >> Are you aware of the pager rework in [0]? I'm considering to review and > >> merge these changes. It may make sense t

multi-client libpager

Hi - Just a quick FYI to let you all know that I'm working on a multi-client libpager. This will allow execution of binaries on remote nodes in a Hurd cluster. I'm well into pseudo coding the logic; you can follow my work in the netmsg github repository:

Re: [GSoC 2017] Support for fsysopts and multiple interfaces

Joan - Thank you for your work on this. I haven't commented on it until now, partly because of some email problems, and partly because I haven't been working on Hurd for the last six months or so. On Mon, Jun 26, 2017 at 7:28 AM, Joan Lledó wrote: > I've advanced in

Re: [GSoC 2017] Support for fsysopts and multiple interfaces

On Thu, Jun 29, 2017 at 7:13 AM, Joan Lledó wrote: > Hello Brent, > > Thanks for your interest in my GSoC. I didn't know the tools you > propose and think that everything that moves us towards using > standards is good. What I believe is that probably such a development

multi page memory object operations

Hi - I've found something puzzling while working on the libpager code. It seems that the current libpager's data-request and data-unlock routines only handle single page requests, while the Mach documentation suggests that the kernel can make multi page requests using these routines. Looking at

libpager

Hi - I've learned some interesting things about libpager that I'd like to share with the list. I've found two bugs in the existing code that were "fixed" by the new demuxer that sequentially services requests on each pager object. For example, the data return code sets a flag PAGINGOUT in the

Re: libpager

On Sun, Aug 6, 2017 at 12:40 PM, Justus Winter <jus...@gnupg.org> wrote: > "Brent W. Baccala" <cos...@freesoft.org> writes: > > > but it's obviously got some issues > > What kind of issues? > I was thinking of a multi-client environment where a disk

possible recent performance change?

Hi - I recently updated my Debian Hurd system for the first time in a few months, and it started showing an annoying behavior running emacs over ssh, from an Ubuntu host to Hurd on a qemu VM. The editor would freeze for about a second, then suddenly catch up with the key strokes I had typed in

libpager pagemap

Hi - My work on a multi-client libpager has progressed to the point where I have pseudo code for the logic and am considering how to implement the pagemap. I'm trying to achieve three goals with the pagemap: 1. keep pagemap entries as small as possible 2. support arbitrary numbers of clients,

Re: hurd vm images don't seem to be booting

On Wed, Dec 13, 2017 at 3:39 AM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Hello, > > Brent W. Baccala, on mar. 12 déc. 2017 20:53:05 -0500, wrote: > > qemu-system-i386 -enable-kvm -m 1024 -nographic -drive file= > > debian-hurd-20171101.img,format=raw >

hurd vm images don't seem to be booting

Hi - I've downloaded Hurd images from these two locations: http://cdimage.debian.org/cdimage/ports/current/hurd-i386/debian-hurd.img.tar.gz http://people.debian.org/~sthibault/hurd-i386/debian-hurd.img.tar.gz and I've had the same problem with both. I can't get the grub boot menu to load with

Re: race condition destroying condition variables

On Tue, Dec 19, 2017 at 3:25 AM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Brent W. Baccala, on mar. 19 déc. 2017 00:08:44 -0500, wrote: > > Looks like there's a race condition when we destroy a condition > variable. My > > understanding of the expected b

race condition destroying condition variables

Hi - Looks like there's a race condition when we destroy a condition variable. My understanding of the expected behavior is that once all the threads have been signaled (i.e, pthread_cond_broadcast is called), the condition variable can be safely destroyed with pthread_cond_destroy. The problem

race condition in libports

Hi - I'm making good progress on the multi-client libpager. I've been running it on my root filesystem for about a month now, with few problems recently. However, there are still some bugs. One seems to be in libports. It manifests like this: /hurd/ext2fs.static:

Re: race condition in libports

On Sun, Dec 17, 2017 at 8:02 AM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Hello, > > Brent W. Baccala, on sam. 16 déc. 2017 21:37:05 -0500, wrote: > > basically, we're storing ports in a inode-to-port hash, looking them > > up when io_identity() gets cal

Re: SIGILL problems with Hurd port of GO in gcc-8, and rpctrace bugs.

On Wed, Nov 15, 2017 at 11:53 AM, Svante Signell wrote: > > Additionally the rpctrace output hangs hard at gsync_wait() both for the > ./index0-out-reduced_OK.x and ./index0-out-reduced_nOK.x files. > Has rpctrace been thoroughly tested on multi-thread applications? > >

Re: SIGILL problems with Hurd port of GO in gcc-8, and rpctrace bugs.

On Fri, Nov 17, 2017 at 3:14 PM, Svante Signell wrote: > > Thanks a lot for your patches for rpctrace. Now more failing programs > can be traced, where the standard version fails. There are still some > examples hanging hard on gsync_wait or entering an infinite loop. >

Re: FSF copyright assignment (was: SIGILL problems with Hurd port of GO in gcc-8, and rpctrace bugs)

On Mon, Nov 20, 2017 at 3:33 AM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Brent W. Baccala, on dim. 19 nov. 2017 20:04:35 -0500, wrote: > > The assignment of par. 1(a) above applies to all > > past and future w

Re: SIGILL problems with Hurd port of GO in gcc-8, and rpctrace bugs.

On Thu, Nov 16, 2017 at 12:39 PM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Hello, > > Brent W. Baccala, on jeu. 16 nov. 2017 12:25:23 -0500, wrote: > > This isn't in the main Hurd repository because I wouldn't sign the FSF > > copyright assignment. They insis

Re: SIGILL problems with Hurd port of GO in gcc-8, and rpctrace bugs.

On Thu, Nov 16, 2017 at 5:55 PM, Svante Signell wrote: > > > Perhaps you could try those patches and see if they fix your problem? > If not, > > then it's something else that should be investigated further. > > Thanks, I will try to apply them: Do I need all 0001 to

Re: race condition destroying condition variables

On Wed, Dec 27, 2017 at 2:31 PM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Hello, > > Brent W. Baccala, on mar. 26 déc. 2017 23:06:13 -0500, wrote: > > Also, the Linux source code in nptl/ includes the following comment: > > > > /* If there are waiters

Re: race condition in libports

On Sun, Dec 17, 2017 at 11:41 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > On Sun, Dec 17, 2017 at 8:02 AM, Samuel Thibault <samuel.thiba...@gnu.org> > wrote: > >> Hello, >> >> Brent W. Baccala, on sam. 16 déc. 2017 21:37:05 -0500, wrote: >>

Re: race condition in libports

On Fri, Jan 5, 2018 at 7:24 PM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Hello, > > Brent W. Baccala, on ven. 05 janv. 2018 17:45:57 -0500, wrote: > > I've "fixed" this by making sure we don't remove the hash table entry > unless > > there are

Re: race condition destroying condition variables

Well, I've got a patch that might work, but I'm having a lot of trouble testing it. I can't dpkg-buildpackage the Debian glibc package. It gets into the test routines, then a bunch of the math tests crash with SIGSEGVs and SIGILLs, then I get a bunch of kernel errors: no more room in ee26a908

Hurd lecture

Hi - FYI, I gave an hour and a half Hurd lecture yesterday at Catholic University in Washington, D.C. I put a screencast of the lecture on youtube: https://www.youtube.com/watch?v=JwsuAEF2FYE The first part of the video is a general discussion of high performance computing, leading into my own

Re: Hurd lecture

On Fri, Jan 19, 2018 at 4:47 AM, Thomas Schwinge wrote: > > Could we add that to the collection of presentations that we've got on > the > > documentation page? > > If you'd like to, you can add it yourself using the wiki interface at >

Re: Hurd lecture

On Fri, Jan 19, 2018 at 7:35 AM, Ricardo Wurmus wrote: > > Hi Brent, > > > I put a screencast of the lecture on youtube: > > > > https://www.youtube.com/watch?v=JwsuAEF2FYE > > thank you. This was very interesting. The introduction to Mach IPC and > memory management was

libpager, proc server, rpctrace, and other meandering

Hi - I'm writing to update the list on my current work and possibly get some useful suggestions. I'm trying to test the multi-client libpager in a subhurd, but I'm having problems even getting the old libpager code to work cleanly in a subhurd, so I know I've got problems that aren't just in my

Re: glibc / proc server interaction

On Mon, Feb 5, 2018 at 2:42 PM, Brent W. Baccala <cos...@freesoft.org> wrote: > On Mon, Feb 5, 2018 at 1:51 AM, Samuel Thibault <samuel.thiba...@gnu.org> > wrote: > >> Hello, >> >> Brent W. Baccala, on lun. 05 févr. 2018 00:35:17 -0500, wrote: >> >

attaching rpctrace to running processes

Hi - I've modified rpctrace to attach to running processes and trace them. I've added a new set of patches (the 0200 series) to my github repository with these changes. I'm still chasing bugs, and it can't detach from processes without killing them, but it's basically working. The only big

gnumach debugger advice

Hi - Can anybody advice me how to use the gnumach debugger for a particular case? I've got a subhurd's proc server that is blocked in the kernel RPC processor_set_tasks(). That thread is holding a global lock in the proc server and locking up the program while waiting for the RPC to return,

Re: gnumach debugger advice

On Sun, Feb 11, 2018 at 4:42 AM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Brent W. Baccala, on dim. 11 févr. 2018 01:23:10 -0500, wrote: > > So how can I figure out where in processor_set_tasks() (or its > subroutines) > > that the kernel has blocked? > >

Re: race condition destroying condition variables

Well, I've tried both Samuel's (swap space) and Svante's (nocheck) suggestions and have found that both allow me to successfully build the glibc packages! The problem that I've got now is that I've changed the size of the condition variables by adding an extra field, an integer that tracks the

RFC: kernel trace facility

I've had so many problems with rpctrace that I'm starting work on a kernel trace facility, and I think the consensus on this list is that we need something like this. Here's the idea. Add a trace port as a new task special port. The same RPCs that get/set task ports and exception ports will be

Re: Personal Introduction

On Thu, Apr 5, 2018 at 6:53 PM, Samuel Thibault <samuel.thiba...@gnu.org> wrote: > Brent W. Baccala, le jeu. 05 avril 2018 18:42:24 -0400, a ecrit: > > > that the Debian maintainers have threatened to drop us completely unless > we get > > our code upstreamed in

Re: Personal Introduction

On Thu, Apr 5, 2018 at 11:20 AM, Charlie Sale wrote: > Hey Brent > > I would be willing to help with that project. I'll see what I can do to > contribute. > > You said that you had some code written. Where can I find it? Is it in a > branch on the main tree? > No,

  1   2   >