From a1cae31c1c34661bbd172d9e555e71521ce863cd Mon Sep 17 00:00:00 2001 From: Mauricio Faria de Oliveira Date: Wed, 10 Jan 2018 23:40:07 +0530 Subject: [PATCH 16/26] UBUNTU: SAUCE: rfi-flush: Fix kernel package build using bootmem CVE-2017-5754 This introduces functional changes, see comment in file. Build error: arch/powerpc/kernel/setup_64.c: In function 'init_fallback_flush': arch/powerpc/kernel/setup_64.c:823:6: error: the address of 'l1d_flush_fallback_area' will always evaluate as 'true' [-Werror=address] if (l1d_flush_fallback_area) ^ cc1: all warnings being treated as errors make[1]: *** [arch/powerpc/kernel/setup_64.o] Error 1 Signed-off-by: Mauricio Faria de Oliveira Signed-off-by: Stefan Bader --- arch/powerpc/kernel/setup_64.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index d9ca1c6..f7956b3 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -778,16 +778,16 @@ static bool init_fallback_flush(void) u64 l1d_size; int cpu; - if (l1d_flush_fallback_area) - return true; - /* - * Once the slab allocator is up it's too late to allocate the fallback - * flush area, so return an error. This could happen if we migrated from - * a patched machine to an unpatched machine. + * On distros using bootmem, l1d_flush_fallback area is always allocated + * (in BSS) and valid, so skip the checks for l1d_flush_fallback_area and + * slab_is_available(). + * + * Possibly it's not even needed to do any of the rest of this function + * _again_ (can anything set below can changed after LPM/other system?), + * but keep it simple and don't try to different first from future calls, + * just run it again in that case. */ - if (slab_is_available()) - return false; l1d_size = ppc64_caches.dsize; -- 2.7.4