From cbeab2cd991929815f50ee995a593db1ab07bf6e Mon Sep 17 00:00:00 2001 From: Stijn Tintel Date: Sun, 7 Nov 2021 18:33:35 +0200 Subject: [PATCH] kernel: add another missing KASAN symbol Enabling KERNEL_KASAN exposes yet another missing symbol. This did not appear on bcm27xx but is appearing now on x86/64. Add a new kernel build option for KASAN_VMALLOC to fix build on x86/64 with KERNEL_KASAN enabled. Signed-off-by: Stijn Tintel Acked-by: Hauke Mehrtens --- config/Config-kernel.in | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/config/Config-kernel.in b/config/Config-kernel.in index 902e211ea1..f5b42b71ee 100644 --- a/config/Config-kernel.in +++ b/config/Config-kernel.in @@ -170,6 +170,22 @@ config KERNEL_KASAN_EXTRA compile time. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more +CONFIG KERNEL_KASAN_VMALLOC + bool "Back mappings in vmalloc space with real shadow memory" + depends on KERNEL_KASAN + By default, the shadow region for vmalloc space is the read-only + zero page. This means that KASAN cannot detect errors involving + vmalloc space. + + Enabling this option will hook in to vmap/vmalloc and back those + mappings with real shadow memory allocated on demand. This allows + for KASAN to detect more sorts of errors (and to support vmapped + stacks), but at the cost of higher memory usage. + + This option depends on HAVE_ARCH_KASAN_VMALLOC, but we can't + depend on that in here, so it is possible that enabling this + will have no effect. + if KERNEL_KASAN config KERNEL_KASAN_GENERIC def_bool y -- 2.30.2