On Mon, Dec 19, 2016 at 12:04:54PM +0000, Matt Redfearn <matt.redfearn@xxxxxxxxxx> wrote: Hello Matt. > Hi Serge, > > > On 19/12/16 02:07, Serge Semin wrote: > >It's useful to have some printed map of the kernel virtual memory, > >at least for debugging purpose. > > > >Signed-off-by: Serge Semin <fancer.lancer@xxxxxxxxx> > >--- > > arch/mips/mm/init.c | 47 +++++++++++++++++++++++++++++++++++ > > 1 file changed, 47 insertions(+) > > > >diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c > >index 13a032f..35e7ba8 100644 > >--- a/arch/mips/mm/init.c > >+++ b/arch/mips/mm/init.c > >@@ -32,6 +32,7 @@ > > #include <linux/hardirq.h> > > #include <linux/gfp.h> > > #include <linux/kcore.h> > >+#include <linux/sizes.h> > > #include <asm/asm-offsets.h> > > #include <asm/bootinfo.h> > >@@ -106,6 +107,49 @@ static void __init zone_sizes_init(void) > > } > > /* > >+ * Print out kernel memory layout > >+ */ > >+#define MLK(b, t) b, t, ((t) - (b)) >> 10 > >+#define MLM(b, t) b, t, ((t) - (b)) >> 20 > >+#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) > >+static void __init mem_print_kmap_info(void) > >+{ > >+ pr_notice("Virtual kernel memory layout:\n" > >+ " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" > >+ " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" > >+#ifdef CONFIG_HIGHMEM > >+ " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n" > >+#endif > >+ " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" > >+ " .text : 0x%p" " - 0x%p" " (%4td kB)\n" > >+ " .data : 0x%p" " - 0x%p" " (%4td kB)\n" > >+ " .init : 0x%p" " - 0x%p" " (%4td kB)\n", > >+ MLM(PAGE_OFFSET, (unsigned long)high_memory), > >+ MLM(VMALLOC_START, VMALLOC_END), > >+#ifdef CONFIG_HIGHMEM > >+ MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP)*(PAGE_SIZE)), > >+#endif > >+ MLK(FIXADDR_START, FIXADDR_TOP), > >+ MLK_ROUNDUP(_text, _etext), > >+ MLK_ROUNDUP(_sdata, _edata), > >+ MLK_ROUNDUP(__init_begin, __init_end)); > > Please drop printing the kernel addresses, or at least only do it if KASLR > is not turned on, otherwise you're removing the advantage of KASLR, that > critical kernel addresses cannot be determined easily from userspace. > > It may be better to merge the functionality of show_kernel_relocation > http://lxr.free-electrons.com/source/arch/mips/kernel/relocate.c#L354 > into this function, but only print it under the same conditions as > currently, i.e. > #if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO) > http://lxr.free-electrons.com/source/arch/mips/kernel/setup.c#L530 > > Thanks, > Matt > Understood. Will be fixed within the next patchset. > >+ > >+ /* Check some fundamental inconsistencies. May add something else? */ > >+#ifdef CONFIG_HIGHMEM > >+ BUILD_BUG_ON(VMALLOC_END < PAGE_OFFSET); > >+ BUG_ON(VMALLOC_END < (unsigned long)high_memory); > >+#endif > >+ BUILD_BUG_ON((PKMAP_BASE) + (LAST_PKMAP)*(PAGE_SIZE) < PAGE_OFFSET); > >+ BUG_ON((PKMAP_BASE) + (LAST_PKMAP)*(PAGE_SIZE) < > >+ (unsigned long)high_memory); > >+ BUILD_BUG_ON(FIXADDR_TOP < PAGE_OFFSET); > >+ BUG_ON(FIXADDR_TOP < (unsigned long)high_memory); > >+} > >+#undef MLK > >+#undef MLM > >+#undef MLK_ROUNDUP > >+ > >+/* > > * Not static inline because used by IP27 special magic initialization code > > */ > > void setup_zero_pages(void) > >@@ -492,6 +536,9 @@ void __init mem_init(void) > > /* Free highmemory registered in memblocks */ > > mem_init_free_highmem(); > >+ /* Print out kernel memory layout */ > >+ mem_print_kmap_info(); > >+ > > /* Print out memory areas statistics */ > > mem_init_print_info(NULL); > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html