Re: compat_linux(8) has 2GB filesize limit in 4.2-stable
Philip Guenther wrote: On Feb 5, 2008 6:27 PM, Glenn Mulvaney [EMAIL PROTECTED] wrote: I'm running a linux binary via compat_linux(8) built from ports/emulators/fedora in 4.2-stable. Emulated binaries can't create or read files 2GB regardless of limits or login class. Does anyone have advice on how to remove this limit? Can that Linux binary create and read files larger than 2GB on a *Linux* system? If it doesn't use 64bit capable syscalls, then there's nothing the BSD compat layer can do about it. As a counter-example, a quick check shows that a 'cat' binary from RHEL AS 4 has no problems with a file over 4GB in size, but strace/ktrace show that it uses the Linux fstat64() call, etc. (Hmm, do the compat_linux versions of the 32bit-only syscalls return EOVERFLOW like the Linux ones would on files 2GB? I don't _see_ code to check that...) The binary definitely can create read files larger than 2GB on a linux system. It's the p4d binary from Perforce under emulation that I'm having a problem with. The 64bit calls are in the compat layer (/usr/src/sys/compat/linux/linux_file64.c) ktrace shows calls to fstat64(), but pread() segvs on p4d reading files larger than 2GB, and pwrite() segvs on p4d writing files larger than 2GB. -Glenn
Re: compat_linux(8) has 2GB filesize limit in 4.2-stable
The binary definitely can create read files larger than 2GB on a linux system. It's the p4d binary from Perforce under emulation that I'm having a problem with. The 64bit calls are in the compat layer (/usr/src/sys/compat/linux/linux_file64.c) ktrace shows calls to fstat64(), but pread() segvs on p4d reading files larger than 2GB, and pwrite() segvs on p4d writing files larger than 2GB. -Glenn COMPAT_LINUX emulation of pread() and pwrite() system calls is limited to 32-bit file offsets. However, Linux kernels eventually changed these system calls to use 64-bit file offsets (without using a different system call number, unfortunately). The COMPAT_LINUX code is in dire need of an upgrade to match more recent linux kernels... Miod
Re: compat_linux(8) has 2GB filesize limit in 4.2-stable
The COMPAT_LINUX code is in dire need of an upgrade to match more recent linux kernels... I certainly agree. For example, I need to compile a custom OpenBSD kernel with this patch http://marc.info/?l=openbsd-miscm=119479722118605 just to get certain programs running under compat_linux.
compat_linux(8) has 2GB filesize limit in 4.2-stable
I'm running a linux binary via compat_linux(8) built from ports/emulators/fedora in 4.2-stable. Emulated binaries can't create or read files 2GB regardless of limits or login class. Does anyone have advice on how to remove this limit? -Glenn
Re: compat_linux(8) has 2GB filesize limit in 4.2-stable
On Feb 5, 2008 6:27 PM, Glenn Mulvaney [EMAIL PROTECTED] wrote: I'm running a linux binary via compat_linux(8) built from ports/emulators/fedora in 4.2-stable. Emulated binaries can't create or read files 2GB regardless of limits or login class. Does anyone have advice on how to remove this limit? Can that Linux binary create and read files larger than 2GB on a *Linux* system? If it doesn't use 64bit capable syscalls, then there's nothing the BSD compat layer can do about it. As a counter-example, a quick check shows that a 'cat' binary from RHEL AS 4 has no problems with a file over 4GB in size, but strace/ktrace show that it uses the Linux fstat64() call, etc. (Hmm, do the compat_linux versions of the 32bit-only syscalls return EOVERFLOW like the Linux ones would on files 2GB? I don't _see_ code to check that...) Philip Guenther
