On Thu, 27 Dec 2007, Vamsee Priya wrote: > Hi > > I have tried LD_PRELOAD and UMEM_DEBUG with my program on Sparc. > Everything worked. I also am unable to find any bug in my program. > > No clue as to who is the culprit..
Are you willing to share the coredump, and/or the application sourcecode (for the function active_out to start with) ? Thx, FrankH. > > Thanks > Priya > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: Wednesday, December 26, 2007 6:52 PM > To: Vamsee Priya > Cc: [EMAIL PROTECTED]; opensolaris-discuss@opensolaris.org > Subject: Re: [osol-discuss] SIGSEGV in > libc.so.1`_malloc_unlockedonSolarisx86machine > > > > On Wed, 26 Dec 2007, Vamsee Priya wrote: > >> Hi, >> >>> From the umem_status I too agree that some thing in my program > corrupted >> the memory. I am working on as to what caused the problem. The same >> program works fine always in "SPARC" platform. Why is it that it is >> causing problems on x86 architecture only? > > There are differences between CPU architectures that go beyond "this is > 32bit this is 64bit". Again, data structure alignment/padding rules and > operand sizes come to mind. > > Have you ever run your program on SPARC with libumem/UMEM_DEBUG ? It > might > well fail in the same way (under memory debugging). As said, whether a > bug > such as this causes a program failure or not "depends" - on how lucky > you > are :) > > From the stacktraces you have, the function active_out() is the place to > > look. You allocate a piece of memory there, do something with it and in > the process of that overwrite the buffer beyond its end, and then you > try > to free it. That's when libumem tells you "oh no, not with me ... I know > > what you did ...". > > FrankH. > >> >> Thanks >> Priya >> >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf >> Of [EMAIL PROTECTED] >> Sent: Wednesday, December 26, 2007 6:36 PM >> To: Vamsee Priya >> Cc: opensolaris-discuss@opensolaris.org >> Subject: Re: [osol-discuss] SIGSEGV in libc.so.1`_malloc_unlocked >> onSolarisx86machine >> >> >> >>> This is the o/p I get with umem_status when I attach mdb to the > process >>> running. >>> >>> Status: ready and active >>> Concurrency: 0 >>> Logs: (inactive) >>> Message buffer: >>> umem allocator: redzone violation: write past end of buffer >>> buffer=80c7c68 bufctl=80c8ce8 cache: umem_alloc_80 >> >> This error basically says: you have allocated an "X" (<= 80 bytes) of >> memory but you wrote more than 80 bytes in that buffer. >> >> The buffer was allocated from this point in your application: >> >>> previous transaction on buffer 80c7c68: >>> thread=1 time=T-0.000415973 slab=80b8ed8 cache: umem_alloc_80 >>> libumem.so.1'?? (0xfef99a48) >>> libumem.so.1'umem_cache_alloc+0xe1 >>> libumem.so.1'umem_alloc+0x3f >>> libumem.so.1'malloc+0x23 >>> ipfs_diff.exe'get_meta+0x28e <--- here >>> ipfs_diff.exe'active_out+0xb5 >>> ipfs_diff.exe'active+0xe0 >>> ipfs_diff.exe'main+0xd59 >>> ipfs_diff.exe'_start+0x80 >> >> >> And was freed here at which point the corruption was detected. >> >>> umem: heap corruption detected >>> stack trace: >>> libumem.so.1'?? (0xfef96099) >>> libumem.so.1'?? (0xfef98b1c) >>> libumem.so.1'umem_free+0xf6 >>> libumem.so.1'?? (0xfef97c05) >>> libumem.so.1'free+0x14 >>> ipfs_diff.exe'meta_free+0xbf >>> ipfs_diff.exe'active_out+0x44e >>> ipfs_diff.exe'active+0xe0 >>> ipfs_diff.exe'main+0xd59 >>> ipfs_diff.exe'_start+0x80 >> >> You could look at the buffer (+ 0t80) and see what was written there. >> >> Casper >> >> >> >> >> _______________________________________________ >> opensolaris-discuss mailing list >> opensolaris-discuss@opensolaris.org >> > > > ------------------------------------------------------------------------------ No good can come from selling your freedom, not for all the gold in the world, for the value of this heavenly gift far exceeds that of any fortune on earth. ------------------------------------------------------------------------------ _______________________________________________ opensolaris-discuss mailing list opensolaris-discuss@opensolaris.org
