Before this patch, someone who wants to use VMAP_STACK when KASAN_GENERIC enabled must explicitly select KASAN_VMALLOC. >From Will's suggestion [1]: > I would _really_ like to move to VMAP stack unconditionally, and > that would effectively force KASAN_VMALLOC to be set if KASAN is in use. Because VMAP_STACK now depends on either HW_TAGS or KASAN_VMALLOC if KASAN enabled, in order to make VMAP_STACK selected unconditionally, we bind KANSAN_GENERIC and KASAN_VMALLOC together. Note that SW_TAGS supports neither VMAP_STACK nor KASAN_VMALLOC now, so this is the first step to make VMAP_STACK selected unconditionally. Bind KANSAN_GENERIC and KASAN_VMALLOC together is supposed to cost more memory at runtime, thus the alternative is using SW_TAGS KASAN instead. [1]: https://lore.kernel.org/lkml/20210204150100.GE20815@willie-the-truck/ Suggested-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx> --- arch/arm64/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index a8f5a9171a85..9be6a57f6447 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -190,6 +190,7 @@ config ARM64 select IOMMU_DMA if IOMMU_SUPPORT select IRQ_DOMAIN select IRQ_FORCED_THREADING + select KASAN_VMALLOC if KASAN_GENERIC select MODULES_USE_ELF_RELA select NEED_DMA_MAP_STATE select NEED_SG_DMA_LENGTH -- 2.25.1
