Hi Dave, On Fri, Aug 23, 2024 at 2:54 PM Dave Vasilevsky <dave@xxxxxxxxxxxxx> wrote: > Fixes boot failures on 6.9 on PPC_BOOK3S_32 machines using > Open Firmware. On these machines, the kernel refuses to boot > from non-zero PHYSICAL_START, which occurs when CRASH_DUMP is on. > > Since most PPC_BOOK3S_32 machines boot via Open Firmware, it should > default to off for them. Users booting via some other mechanism > can still turn it on explicitly. > > Also defaults to CRASH_DUMP=n on sh. > > Signed-off-by: Dave Vasilevsky <dave@xxxxxxxxxxxxx> > Reported-by: Reimar Döffinger <Reimar.Doeffinger@xxxxxx> > Closes: https://lists.debian.org/debian-powerpc/2024/07/msg00001.html > Fixes: 75bc255a7444 ("crash: clean up kdump related config items") Thanks for your patch! > --- a/kernel/Kconfig.kexec > +++ b/kernel/Kconfig.kexec > @@ -97,7 +97,7 @@ config KEXEC_JUMP > > config CRASH_DUMP > bool "kernel crash dumps" > - default y > + default ARCH_DEFAULT_CRASH_DUMP > depends on ARCH_SUPPORTS_CRASH_DUMP > depends on KEXEC_CORE > select VMCORE_INFO IMHO CRASH_DUMP should just default to n, like most kernel options, as it enables non-trivial extra functionality: the kernel source tree has more than 100 locations that check if CONFIG_CRASH_DUMP is enabled. Letting it default to enabled also conflicts with the spirit of the help text for the symbol: Generate crash dump after being started by kexec. This should be normally only set in special crash dump kernels ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ which are loaded in the main kernel with kexec-tools into a specially reserved region and then later executed after a crash by kdump/kexec. The crash dump kernel must be compiled to a memory address not used by the main kernel or BIOS using PHYSICAL_START, or it must be built as a relocatable image (CONFIG_RELOCATABLE=y). For more details see Documentation/admin-guide/kdump/kdump.rst For s390, this option also enables zfcpdump. See also <file:Documentation/arch/s390/zfcpdump.rst> What is so special about CRASH_DUMP, that it should be enabled by default? Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
