On Tue, Jul 24, 2012 at 03:54:10PM +0200, Daniel Kiper wrote: > On Tue, Jul 24, 2012 at 10:18:34AM +0200, Petr Tesarik wrote: > > Dne Po 23. ??ervence 2012 22:10:59 Daniel Kiper napsal(a): > > > Hi Petr, > > > > > > On Mon, Jul 23, 2012 at 03:30:55PM +0200, Petr Tesarik wrote: > > > > Dne Po 23. ??ervence 2012 14:56:07 Petr Tesarik napsal(a): > > > > > Dne ??t 5. ??ervence 2012 14:16:35 Daniel Kiper napsal(a): > > > > > > vmcoreinfo file could exists under /sys/kernel (valid on baremetal > > > > > > only) and/or under /sys/hypervisor (valid when Xen dom0 is running). > > > > > > Read only one of them. It means that only one PT_NOTE will be always > > > > > > created. Remove extra code for second PT_NOTE creation. > > > > > > > > > > Hi Daniel, > > > > > > > > > > are you absolutely sure this is the right thing to do? IIUC these two > > > > > VMCORINFO notes are very different. The one from /sys/kernel/vmcoreinfo > > > > > describes the Dom0 kernel (type 'VMCOREINFO'), while the one from > > > > > /sys/hypervisor describes the Xen hypervisor (type 'XEN_VMCOREINFO'). > > > > > If you keep only the hypervisor note, then e.g. makedumpfile won't be > > > > > able to use dumplevel greater than 1, nor will it be able to extract > > > > > the log buffer. > > > > > > > > I've just verified this, and I'm confident we have to keep both notes in > > > > the dump file. Simon, please revert Daniel's patch to avoid regressions. > > > > > > > > I'm attaching a sample VMCOREINFO_XEN and VMCOREINFO to demonstrate the > > > > difference. Note that the VMCOREINFO_XEN note is actually too big, > > > > because Xen doesn't bother to maintain the correct note size in the note > > > > header, so it always spans a complete page minus sizeof(Elf64_Nhdr)... > > > > > > [...] > > > > > > The problem with /sys/kernel/vmcoreinfo under Xen is that it expose invalid > > > physical address. It breaks /proc/vmcore in crash kernel. That is why I > > > proposed that fix. Additionally, /sys/kernel/vmcoreinfo is not available > > > under Xen Linux Ver. 2.6.18. However, I did not do any makedumpfile tests. > > > If you discovered any issues with my patch please drop me more details > > > about your tests (Xen version, Linux Kernel version, makedumpfile version, > > > command lines, config files, logs, etc.). I will be more then happy to > > > fix/improve kexec-tools and makedumpfile. > > > > Hi Daniel, > > > > well, Linux v2.6.18 does not have /sys/kernel/vmcoreinfo, simply because the > > VMCOREINFO infrastructure was not present in 2.6.18. It was added later with > > Yep. > > > commit fd59d231f81cb02870b9cf15f456a897f3669b4e, which went into 2.6.24. > > Hmmm... As I know 2.6.24 does not support kexec/kdump under Xen dom0. Correct? > > > I tested with the following combinations: > > > > * xen-3.3.1 + kernel-xen-2.6.27.54 + kexec-tools-2.0.0 + makedumpfile-1.3.1 > > * xen-4.0.3 + kernel-xen-2.6.32.59 + kexec-tools-2.0.0 + makedumpfile-1.3.1 > > * xen-4.1.2 + kernel-xen-3.0.34 + kexec-tools-2.0.0 + makedumpfile-1.4.0 > > > > These versions correspond to SLES11-GA, SLES11-SP1 and SLES11-SP2, > > respectively. All of them work just fine and save both ELF notes into the > > dump. > > Could you test current kexec-tools development version and > latest makedumpfile version on latest SLES version? > > > What do you mean by "invalid physical address"? I'm getting the correct > > physical address under Xen. Obviously, it must be translated to machine > > addresses if you need them from the secondary kernel. > > Correct vmcoreinfo address should be established by calling > HYPERVISOR_kexec_op(KEXEC_CMD_kexec_get_range, KEXEC_RANGE_MA_VMCOREINFO). > Address exposed by /sys/kernel/vmcoreinfo is calculated in other way. > /sys/hypervisor/vmcoreinfo does it correctly (in older implementations > and in my new upstream implementation which I am going to post shortly). > > > Anyway, let me re-install my test system and send all the necessary > > information. What kind of log files are you interested in? > > If you spot any error in any logfile which in your opinion > is relevent to our testes please send me it. Hi, is there any consensus on what to do here?
