Re: [RFC PATCH 03/10] powerpc: introduce kimage_vaddr to store the kernel base

[Christophe Leroy]

Le 17/07/2019 à 10:06, Jason Yan a écrit :

Now the kernel base is a fixed value - KERNELBASE. To support KASLR, we
need a variable to store the kernel base.

Signed-off-by: Jason Yan <yanai...@huawei.com>
Cc: Diana Craciun <diana.crac...@nxp.com>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Christophe Leroy <christophe.le...@c-s.fr>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Nicholas Piggin <npig...@gmail.com>
Cc: Kees Cook <keesc...@chromium.org>

Reviewed-by: Christophe Leroy <christophe.le...@c-s.fr>

---
  arch/powerpc/include/asm/page.h | 2 ++
  arch/powerpc/mm/init-common.c   | 2 ++
  2 files changed, 4 insertions(+)

diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 0d52f57fca04..60a68d3a54b1 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -315,6 +315,8 @@ void arch_free_page(struct page *page, int order);

struct vm_area_struct; +extern unsigned long kimage_vaddr;

+
  #include <asm-generic/memory_model.h>
  #endif /* __ASSEMBLY__ */
  #include <asm/slice.h>
diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c
index 9273c38009cb..c7a98c73e5c1 100644
--- a/arch/powerpc/mm/init-common.c
+++ b/arch/powerpc/mm/init-common.c
@@ -25,6 +25,8 @@ phys_addr_t memstart_addr = (phys_addr_t)~0ull;
  EXPORT_SYMBOL(memstart_addr);
  phys_addr_t kernstart_addr;
  EXPORT_SYMBOL(kernstart_addr);
+unsigned long kimage_vaddr = KERNELBASE;
+EXPORT_SYMBOL(kimage_vaddr);

static bool disable_kuep = !IS_ENABLED(CONFIG_PPC_KUEP);

  static bool disable_kuap = !IS_ENABLED(CONFIG_PPC_KUAP);