Hi,
In a recent post ( http://lwn.net/Articles/360312/ ), Theo de Raadt is criticising Linux page 0 handling. He argue that Linux allows page 0 mapping only for Wine. And OpenBSD won't allow page 0 mapping for security reasons (and performance reasons).
Since Wine seems to be working on other *BSD and derivative systems, is this a problem ?
Could someone comment on this issue. I don't find anything related on http://wiki.winehq.org/OpenBSD
Regards.
On Thu, Nov 05, 2009 at 02:21:47PM +0100, Yann Droneaud wrote:
Hi,
In a recent post ( http://lwn.net/Articles/360312/ ), Theo de Raadt is criticising Linux page 0 handling. He argue that Linux allows page 0 mapping only for Wine. And OpenBSD won't allow page 0 mapping for security reasons (and performance reasons).
Since Wine seems to be working on other *BSD and derivative systems, is this a problem ?
Could someone comment on this issue. I don't find anything related on http://wiki.winehq.org/OpenBSD
Its actually not a real problem for Wine, last years code works without NULL pages.
Our DOS emulator requires it, as vm86() mode uses 0 based mapping, so DOS programs won't work afterwards. But otherwise I see no dependency. (Perhaps Win16, but I dont think so.)
Ciao, Marcus
Le jeudi 05 novembre 2009 à 17:01 +0100, Marcus Meissner a écrit :
On Thu, Nov 05, 2009 at 02:21:47PM +0100, Yann Droneaud wrote:
Hi,
In a recent post ( http://lwn.net/Articles/360312/ ), Theo de Raadt is criticising Linux page 0 handling. He argue that Linux allows page 0 mapping only for Wine. And OpenBSD won't allow page 0 mapping for security reasons (and performance reasons).
Since Wine seems to be working on other *BSD and derivative systems, is this a problem ?
Could someone comment on this issue. I don't find anything related on http://wiki.winehq.org/OpenBSD
Its actually not a real problem for Wine, last years code works without NULL pages.
It seems many people thinks Wine needs to mmap the page 0 to run common application.
Does Wine 1.0 need it ?
If not, it's really a myth.
Our DOS emulator requires it, as vm86() mode uses 0 based mapping, so DOS programs won't work afterwards. But otherwise I see no dependency. (Perhaps Win16, but I dont think so.)
According to this post from Alexandre Julliard, win16 don't need it.
http://old.nabble.com/Re%3A-vm86-mode-is-not-supported-p23884662.html
Perhaps it could be good point if there's a way to disable DOS emulator at build time ?
Regards
On Thu, Nov 05, 2009 at 05:31:52PM +0100, Yann Droneaud wrote:
Le jeudi 05 novembre 2009 à 17:01 +0100, Marcus Meissner a écrit :
On Thu, Nov 05, 2009 at 02:21:47PM +0100, Yann Droneaud wrote:
Hi,
In a recent post ( http://lwn.net/Articles/360312/ ), Theo de Raadt is criticising Linux page 0 handling. He argue that Linux allows page 0 mapping only for Wine. And OpenBSD won't allow page 0 mapping for security reasons (and performance reasons).
Since Wine seems to be working on other *BSD and derivative systems, is this a problem ?
Could someone comment on this issue. I don't find anything related on http://wiki.winehq.org/OpenBSD
Its actually not a real problem for Wine, last years code works without NULL pages.
It seems many people thinks Wine needs to mmap the page 0 to run common application.
Does Wine 1.0 need it ?
If not, it's really a myth.
I installed 1.0.1 , enabled mmap_min_addr protectionm ...
Testcase: Firefox 3.5.4 ... installs and runs nicely. (OK, I had some crashes after Flash Player installation for youtube, but youtube plays).
According to this post from Alexandre Julliard, win16 don't need it.
http://old.nabble.com/Re%3A-vm86-mode-is-not-supported-p23884662.html
Perhaps it could be good point if there's a way to disable DOS emulator
o> at build time ?
You do not know that at build time. My WINE rpms build for i586 can be run on i586 and x86_64 machines.
Ciao, Marcus
On Thursday 05 November 2009 18:31:52 Yann Droneaud wrote:
Le jeudi 05 novembre 2009 à 17:01 +0100, Marcus Meissner a écrit :
On Thu, Nov 05, 2009 at 02:21:47PM +0100, Yann Droneaud wrote:
Hi,
In a recent post ( http://lwn.net/Articles/360312/ ), Theo de Raadt is criticising Linux page 0 handling. He argue that Linux allows page 0 mapping only for Wine. And OpenBSD won't allow page 0 mapping for security reasons (and performance reasons).
Since Wine seems to be working on other *BSD and derivative systems, is this a problem ?
Could someone comment on this issue. I don't find anything related on http://wiki.winehq.org/OpenBSD
Its actually not a real problem for Wine, last years code works without NULL pages.
It seems many people thinks Wine needs to mmap the page 0 to run common application.
Does Wine 1.0 need it ?
If not, it's really a myth.
# sysctl vm.mmap_min_addr vm.mmap_min_addr = 4096
and wine works like a charm.
Our DOS emulator requires it, as vm86() mode uses 0 based mapping, so DOS programs won't work afterwards. But otherwise I see no dependency. (Perhaps Win16, but I dont think so.)
I've never been able to run a dos program in Wine, but I've never asked myself why because I always had an alternative.
According to this post from Alexandre Julliard, win16 don't need it.
http://old.nabble.com/Re%3A-vm86-mode-is-not-supported-p23884662.html
Perhaps it could be good point if there's a way to disable DOS emulator at build time ?
2009/11/5 Mihai Donțu mihai.dontu@gmail.com:
I've never been able to run a dos program in Wine, but I've never asked myself why because I always had an alternative.
DOSbox is a much better DOS than Wine is ever likely to be.
Do Win32 console apps run okay in Wine without the page 0 mapping? I ask because in my last job, we actually used Wine to run a Win32 console app on RHEL4 to save installing another Windows box. Never let anyone tell you Wine isn't ready for the enterprise ;-)
- d.
On Thursday 05 November 2009 19:44:47 David Gerard wrote:
2009/11/5 Mihai Donțu mihai.dontu@gmail.com:
I've never been able to run a dos program in Wine, but I've never asked myself why because I always had an alternative.
DOSbox is a much better DOS than Wine is ever likely to be.
Do Win32 console apps run okay in Wine without the page 0 mapping? I
I use wine to run the Microsoft Visual Studio Express compiler (cl.exe). So far I hadn't had any problems.
ask because in my last job, we actually used Wine to run a Win32 console app on RHEL4 to save installing another Windows box. Never let anyone tell you Wine isn't ready for the enterprise ;-)
On Thu, Nov 05, 2009 at 02:21:47PM +0100, Yann Droneaud wrote:
And OpenBSD won't allow page 0 mapping for security reasons (and performance reasons).
Since Wine seems to be working on other *BSD and derivative systems, is this a problem ?
NetBSD is likely to disable user space mapping of address 0 some time in the near future - it does have problems with the compatibility code for other unix system binariess though (I can't remember which ones, compat-ultrix might be the one).
David
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David Gerard -
David Laight -
Marcus Meissner -
Mihai Donțu -
Yann Droneaud