Re: Anyone able to verify the fix for (was Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.)

2000-04-19 Thread Matthew Dillon
: :I'll remove (or change) the assertion later this evening :unless I hear protests to the contrary. : :Alan : Sounds like a plan. When you get it committed I'll bring it up on one of my test boxes and run it through the gauntlet. -Matt

Re: Anyone able to verify the fix for (was Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.)

2000-04-18 Thread Alan Cox
I'll remove (or change) the assertion later this evening unless I hear protests to the contrary. Alan To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message

Re: Anyone able to verify the fix for (was Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.)

2000-04-18 Thread Matthew Dillon
: :This patch introduces a new bug. While it does guarantee that :the assertion in vm_object_shadow isn't tripped over, it doesn't :clear the OBJ_ONEMAPPING flag on the newly created shadow object. :(New objects are created with OBJ_ONEMAPPING set.) Consequently, :we'll have two overlapping map

Re: Anyone able to verify the fix for (was Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.)

2000-04-18 Thread Alan Cox
This patch introduces a new bug. While it does guarantee that the assertion in vm_object_shadow isn't tripped over, it doesn't clear the OBJ_ONEMAPPING flag on the newly created shadow object. (New objects are created with OBJ_ONEMAPPING set.) Consequently, we'll have two overlapping mappings to

Anyone able to verify the fix for (was Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.)

2000-04-18 Thread Matthew Dillon
Has Brian or Michael or anyone been able to verify whether my patch below fixes the reported vm_object_shadow panics yet? I'd like to get it committed (or scrapped). -Matt Index: vm_map.c =

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Matthew Dillon
:> I don't think this is an issue. The only double-mapped pages we care :> about are those at the top-level (vm_object's connected directly to a :> vm_map_entry). This is because these are the only pages effected by :> write-faults and copy-on-write issues. :> : :I disagre

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alan Cox
On Sat, Apr 15, 2000 at 08:18:01PM -0700, Matthew Dillon wrote: > :Is there a good reason for not having the vm_object_clear_flag() in > :vm_object_reference()? > > Well, yes... vm_object's are referenced for all sorts of things > temporarily. Everything from a process looking one up te

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alan Cox
On Sat, Apr 15, 2000 at 08:13:20PM -0700, Matthew Dillon wrote: > > :Here's what I worry about: We only clear OBJ_ONEMAPPING on the top-level > :object, and none of its backing objects. Nothing guarantees that these > :backing objects have OBJ_ONEMAPPING cleared. The page that we're "double" >

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Matthew Dillon
:Is there a good reason for not having the vm_object_clear_flag() in :vm_object_reference()? Well, yes... vm_object's are referenced for all sorts of things temporarily. Everything from a process looking one up temporarily to the swap code issuing I/O. None of these references have

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Matthew Dillon
:Here's what I worry about: We only clear OBJ_ONEMAPPING on the top-level :object, and none of its backing objects. Nothing guarantees that these :backing objects have OBJ_ONEMAPPING cleared. The page that we're "double" :mapping may, however, reside in one of its backing objects. This is :bad

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alan Cox
On Sat, Apr 15, 2000 at 06:09:56PM -0400, Brian Fundakowski Feldman wrote: > > I'm still trying to understand this: if you know that the object may > have pages mapped elsewhere, the backing objects recursively inherit > the assumption that it may have parts mapped elsewhere? Umm, just to be

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alan Cox
On Sat, Apr 15, 2000 at 06:12:22PM -0400, Brian Fundakowski Feldman wrote: > On Sat, 15 Apr 2000, Matthew Dillon wrote: > > > Note that the ref_count == 1 test in the vm_object_shadow optimization > > should be left intact. This optimization requires a much stricter set > > of tests

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Brian Fundakowski Feldman
On Sat, 15 Apr 2000, Matthew Dillon wrote: > Note that the ref_count == 1 test in the vm_object_shadow optimization > should be left intact. This optimization requires a much stricter set > of tests because we do not want to assume sharability of an object > if someone else (the

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Brian Fundakowski Feldman
On Sat, 15 Apr 2000, Alan Cox wrote: > > It is totally legal for OBJ_ONEMAPPING to be set even if the ref_count > > is greater then 1. > > Agreed. OBJ_ONEMAPPING actually means that *each page* within the object > is mapped at most once. The object itself may be mapped many times, > as

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Brian Fundakowski Feldman
On Sat, 15 Apr 2000, Matthew Dillon wrote: > [explanation] > > Here is a new patch. Please try it (and get rid of any prior patches > to vm_object.c before applying this one). > Thanks for the reply :) What you say makes sense, so I'll try out this patch as soon as I work out a way t

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alan Cox
On Sat, Apr 15, 2000 at 11:23:11AM -0700, Matthew Dillon wrote: > :Well, first the question must be answered, in an absolute yes or no: > :is it wrong in the first place to have OBJ_ONEMAPPING set with a ref_count > :of more than 1? I'd accept an authoritative answer about this from > :alc, dillo

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alfred Perlstein
* Matthew Dillon <[EMAIL PROTECTED]> [000415 11:32] wrote: > > :On Thu, 13 Apr 2000, Michael Reifenberger wrote: > : > :> Hi, > :> when using a linux java app (SAP PlatinGUI 46Cb2) I get the above panic. > :> FreeBSD -current. Kernel+mods in sync. > :> Linux from ports. Linux-Java-JDK 1.2.2 from

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Matthew Dillon
:Well, first the question must be answered, in an absolute yes or no: :is it wrong in the first place to have OBJ_ONEMAPPING set with a ref_count :of more than 1? I'd accept an authoritative answer about this from :alc, dillon, dyson, or luoqi, who are all very familiar with the new :VM. :-- : Br

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Matthew Dillon
:Further elaboration: : :there is an assumption that it is wrong for OBJ_ONEMAPPING to be set but :not when ref_count > 1. This assumption is defeated in the multiple test :cases we can find. It seems that in the test cases, the common problem :is with (I think mmap()d) memory across multiple p

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Matthew Dillon
:On Thu, 13 Apr 2000, Michael Reifenberger wrote: : :> Hi, :> when using a linux java app (SAP PlatinGUI 46Cb2) I get the above panic. :> FreeBSD -current. Kernel+mods in sync. :> Linux from ports. Linux-Java-JDK 1.2.2 from blackdown as of yesterday. :> Backtrace see crash.txt. Kernelconfig see n

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Brian Fundakowski Feldman
On Sat, 15 Apr 2000, Alfred Perlstein wrote: > Yes, find all places where source->ref_count is incremented and check > for OBJ_ONEMAPPING as well as where OBJ_ONEMAPPING is set. > > Then add some printfs to find the snippet that's incrementing it > to complain when the OBJ_ONEMAPPING bit is set,

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Brian Fundakowski Feldman
On Sat, 15 Apr 2000, Alfred Perlstein wrote: > Yes, find all places where source->ref_count is incremented and check > for OBJ_ONEMAPPING as well as where OBJ_ONEMAPPING is set. > > Then add some printfs to find the snippet that's incrementing it > to complain when the OBJ_ONEMAPPING bit is set,

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Alfred Perlstein
* Brian Fundakowski Feldman <[EMAIL PROTECTED]> [000415 07:07] wrote: > On Thu, 13 Apr 2000, Michael Reifenberger wrote: > > > Hi, > > when using a linux java app (SAP PlatinGUI 46Cb2) I get the above panic. > > FreeBSD -current. Kernel+mods in sync. > > Linux from ports. Linux-Java-JDK 1.2.2 fro

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Michael Reifenberger
On Sat, 15 Apr 2000, Brian Fundakowski Feldman wrote: ... > Do you think you can find a specific set of steps for Alan to reproduce > it? Not without this SAP-GUI in conjuntion with a SAP-System to connect to :-( But then it's easyly reproducable. BTW: with your patch I get on the console during

Re: panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-15 Thread Brian Fundakowski Feldman
On Thu, 13 Apr 2000, Michael Reifenberger wrote: > Hi, > when using a linux java app (SAP PlatinGUI 46Cb2) I get the above panic. > FreeBSD -current. Kernel+mods in sync. > Linux from ports. Linux-Java-JDK 1.2.2 from blackdown as of yesterday. > Backtrace see crash.txt. Kernelconfig see nihil. >

panic: vm_object_shadow: source object has OBJ_ONEMAPPING set.

2000-04-13 Thread Michael Reifenberger
Hi, when using a linux java app (SAP PlatinGUI 46Cb2) I get the above panic. FreeBSD -current. Kernel+mods in sync. Linux from ports. Linux-Java-JDK 1.2.2 from blackdown as of yesterday. Backtrace see crash.txt. Kernelconfig see nihil. Any thoughts anyone? Bye! Michael Reifenberger ^.*Plaut.