On 03/19/24 at 07:24am, chenhaixiang (A) wrote: > Thank you for your reply! > The kernel version on my machine is kernel-5.10, and the kexec-tools version is kexec-tools-2.0.27. > However, my issue seems to be a bit different. On my machine, I can see the crashkernel memory segment in /proc/iomem. However, for some reason, within the address range allocated for crashkernel, there is also a segment marked as 'Reserved' (I'm not sure who marked it). In this scenario, kexec-tools calculates the CRASH MEMORY RANGES incorrectly. > ``` crashkernel region can't be reserved again once it's allocated and reserved in memblock. There must be something wrong with the code. You can try upstream kernel and kexec-tools to see if it exists too. Since you are using an old kernel and could be on a distros, we may not be able to cover it. Sorry about that. If you want to debug to find out the reason, I can help give suggestions. > cat /proc/iomem > 2d4fd058-58ffffff : System RAM > 49000000-58ffffff : Crash kernel > 53cbd000-53ccffff : Reserved > ``` > I'm not sure if the crashkernel memory segment should not include other markings, and if not supported, whether kexec-tools should raise an error. > Thanks > Chen Haixiang > ---------- > On 03/19/24 at 9:38qm, Baoquan He wrote: > > Hi, > > > > On 03/18/24 at 12:00pm, chenhaixiang (A) wrote: > > > Dear kexec Community Members, > > > > > > I encountered an issue while using kexec-tools on my x86_64 machine. > > > When there is a segment marked as 'reserved' within the memory range > > allocated for the crash kernel in /proc/iomem,the output appears as follows: > > > 2d4fd058-60efefff : System RAM > > > 2d4fd058-58ffffff : System RAM > > > 49000000-58ffffff : Crash kernel > > > 53cbd000-53ccffff : Reserved > > > > What kernel are you using? the version of kernel, and kexec-tools? > > > > If you are testing on the latest mainline kernel, you could meet the issue Dave > > have met and fixed in below patch: > > > > [PATCH] x86/kexec: do not update E820 kexec table for setup_data > > https://lore.kernel.org/all/ZeZ2Kos-OOZNSrmO@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ > > T/#u > > > > Thanks > > Baoquan > > > > > > > > The crash_memory_range array will encounter incorrect address ranges: > > > CRASH MEMORY RANGES > > > 000000002d4fd058-0000000048ffffff (0) > > > 0000000053cbd000-0000000048ffffff (1) > > > 0000000059000000-0000000053ccffff (0) > > > > > > Read the code, I noticed that the get_crash_memory_ranges() function > > invokes exclude_region() to handle the splitting of memory regions, but it seems > > unable to properly handle the scenario described above. > > > The code logic is as follows: > > > ... > > > if (start < mend && end > mstart) { > > > if (start != mstart && end != mend) { > > > /* Split memory region */ > > > crash_memory_range[i].end = start - 1; > > > temp_region.start = end + 1; > > > temp_region.end = mend; > > > temp_region.type = RANGE_RAM; > > > tidx = i+1; > > > } else if (start != mstart) > > > crash_memory_range[i].end = start - 1; > > > else > > > crash_memory_range[i].start = end + 1; > > > } > > > ... > > > If start < mstart < mend < end, resulting in crash_memory_range[i].end > > becoming less than crash_memory_range[i].start, leading to incorrect address > > ranges. > > > I would like to know if this behavior is reasonable and whether it is necessary to > > validate the address ranges for compliance at the end. > > > > > > Thank you for your time and assistance. > > > > > > Chen Haixiang > > > > > > _______________________________________________ > > > kexec mailing list > > > kexec@xxxxxxxxxxxxxxxxxxx > > > http://lists.infradead.org/mailman/listinfo/kexec > > > > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
