On 05/17/2018 02:21 AM, Adrian Hunter wrote: > From: Alexander Shishkin <[email protected]> > > Signed-off-by: Alexander Shishkin <[email protected]>
For the benefit of the poor souls looking at this code in the decades to come, could you please take a few minutes to write a couple of sentences about why this is being done? > diff --git a/arch/x86/mm/cpu_entry_area.c b/arch/x86/mm/cpu_entry_area.c > index d1da5cf4b2de..fb1fbc8538fa 100644 > --- a/arch/x86/mm/cpu_entry_area.c > +++ b/arch/x86/mm/cpu_entry_area.c > @@ -3,6 +3,7 @@ > #include <linux/spinlock.h> > #include <linux/percpu.h> > #include <linux/kallsyms.h> > +#include <linux/kcore.h> > > #include <asm/cpu_entry_area.h> > #include <asm/pgtable.h> > @@ -14,6 +15,7 @@ > #ifdef CONFIG_X86_64 > static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks > [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]); > +static DEFINE_PER_CPU(struct kcore_list, kcore_entry_trampoline); > #endif > > struct cpu_entry_area *get_cpu_entry_area(int cpu) > @@ -147,6 +149,9 @@ static void __init setup_cpu_entry_area(int cpu) > > cea_set_pte(&get_cpu_entry_area(cpu)->entry_trampoline, > __pa_symbol(_entry_trampoline), PAGE_KERNEL_RX); > + kclist_add(&per_cpu(kcore_entry_trampoline, cpu), > + &get_cpu_entry_area(cpu)->entry_trampoline, PAGE_SIZE, > + KCORE_TEXT); > #endif Any reason not to add a comment like: /* * The cpu_entry_area alias addresses are not in the kernel binary * so they do not show up in /proc/kcore normally. This adds entries * for them manually. */
