* Vlastimil Babka <vbabka@xxxxxxx> wrote: > The kmemleak and debug_pagealloc features both disable using huge pages for > direct mapping so they can do cpa() on page level granularity in any context. > However they only do that for 2MB pages, which means 1GB pages can still be > used if the CPU supports it, unless disabled by a boot param, which is > non-obvious. Disable also 1GB pages when disabling 2MB pages. > > Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> > --- > arch/x86/mm/init.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c > index cbc87ea98751..20282dfce0fa 100644 > --- a/arch/x86/mm/init.c > +++ b/arch/x86/mm/init.c > @@ -170,6 +170,10 @@ static void __init probe_page_size_mask(void) > */ > if (boot_cpu_has(X86_FEATURE_PSE) && !debug_pagealloc_enabled()) > page_size_mask |= 1 << PG_LEVEL_2M; > + else > + direct_gbpages = 0; > +#else > + direct_gbpages = 0; > #endif > > /* Enable PSE if available */ So I agree with the fix, but I think it would be much cleaner to eliminate the outer #ifdef: #if !defined(CONFIG_KMEMCHECK) and put it into the condition, like this: if (boot_cpu_has(X86_FEATURE_PSE) && !debug_pagealloc_enabled() && !IS_ENABLED(CONFIG_KMEMCHECK)) page_size_mask |= 1 << PG_LEVEL_2M; else direct_gbpages = 0; without any #ifdeffery. This makes it much more readable all around, and also makes it obvious that when the 2MB size bit is not set then gbpages are disabled as well. Thanks, Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
