On 2024/03/11 18:08, Tang Yulong wrote: > Hi, Kazu: > >> On 2024/03/01 17:48, Tao Liu wrote: >> >> hmm, as far as I know, not many kernels are configured with >> CONFIG_IKCONFIG=y, e.g. RHEL kernels don't have it. so if it depends >> only on ikconfig, it will not work on many kernels. >> > > Thank you for the correction. > >> It's good to use ikconfig, but isn't there any other way? >> >> For example, it looks like it's always set to y on x86. so maybe we can >> have a default value depending on architecture, for no ikconfig kernels. >> >> config X86 >> ... >> select HAVE_EFFICIENT_UNALIGNED_ACCESS >> >> Thanks, >> Kazu > > Yes, it seems that some architectures have this configuration enabled by default, such as ARM, ARM64, and X86. These are also commonly used architectures. > So setting the default to CONFIG_Y for these architectures and CONFIG_N for others. Then, we can check whether IKCONFIG is enabled to retrieve the actual value. Do you think this is acceptable? > > like this: > > - bool efficient_unaligned_access = (get_kernel_config("CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS", NULL) == IKCONFIG_Y); > + bool efficient_unaligned_access; > + > +#if defined(ARM) || defined(ARM64) || defined(X86) > + efficient_unaligned_access = true; Yes. Looking at arch/*/Kconfig, it looks like the following architectures will have 'y' IIUC, please use these. X86, X86_64, ARM, ARM64, PPC, PPC64, S390, S390X (LOONGARCH64 and RISCV64 can have 'n' depending on configs.) With respect to lzo-rle user library, Tao is asking the kernel developers. (Thanks Tao) Thanks, Kazu > +#else > + efficient_unaligned_access = false; > +#endif > + > + if (kt->ikconfig_flags & IKCONFIG_AVAIL) > + efficient_unaligned_access = (get_kernel_config("CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS", NULL) == IKCONFIG_Y); > > Thanks, > Yulong > -- > Crash-utility mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxxxxxx > To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxxxxxx > https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ > Contribution Guidelines: https://github.com/crash-utility/crash/wiki -- Crash-utility mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxxxxxx https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ Contribution Guidelines: https://github.com/crash-utility/crash/wiki