Hi guys, On 20/06/18 08:26, Bhupesh Sharma wrote: > On Wed, Jun 20, 2018 at 7:46 AM, Jin, Yanjiang > <yanjiang.jin@xxxxxxxxxxxxxxxx> wrote: >> If /proc/kcore always exists in kexec/kdump, I think this issue can be fixed >> easily. But it requires that Kexec/kdump have to rely on " CONFIG_PROC_KCORE=y". >> I am not sure if we can persuade Kexec-tools community to accept this. For the kernel this would be: --------------%<-------------- diff --git a/arch/Kconfig b/arch/Kconfig index 1aa59063f1fd..0ea2c7c0ac08 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -8,6 +8,7 @@ config CRASH_CORE config KEXEC_CORE select CRASH_CORE + select PROC_KCORE bool config HAVE_IMA_KEXEC --------------%<-------------- With this kernel's that support kdump but don't have /proc/kcore wouldn't have the new PT_NOTEs anyway. Whatever you do today is all you can do. > Most distributions like Ubuntu and Fedora already enable > CONFIG_PROC_KCORE by default, to support user-space tools like > crash-utility and makedumpfile which can be used for 'live' debugging > of a primary kernel (without the requirement of being in the secondary > or crash kernel). > > For such cases. '/proc/kcore' and 'vmlinux' are the only available > sources for PT_NOTE/PT_LOAD segments and kernel symbols respectively. > > Since we need to support all such existing user-space utilities (which > work well with other archs like x86 and ppc64), x86 has kaslr too, I couldn't work out how your user-space:phys_to_virt() works there. Are we missing an alternative trick? > we need to have a > solution which works without modifying most of them - the rest (like > kexec-tools) can be easily modified to follow the same approach. (We're also trying to solve this in a way that lets user-space shed arch-specific code.) Thanks, James _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec