lkml.org 
[lkml]   [2008]   [Jan]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH 4/6] x86: fix some bugs about EFI runtime code mapping

* Huang, Ying <ying.huang@intel.com> wrote:

> This patch fixes some bugs of making EFI runtime code executable.
>
> - Use change_page_attr in i386 too. Because the runtime code may be
> mapped not through ioremap.
>
> - If there is no _PAGE_NX in __supported_pte_mask, the change_page_attr
> is not called.
>
> - Make efi_ioremap map pages as PAGE_KERNEL_EXEC, because EFI runtime
> code may be mapped through efi_ioremap.

thanks, applied.

note that here:

> - set_fixmap_nocache(FIX_EFI_IO_MAP_FIRST_PAGE - pages_mapped,
> - offset);
> + __set_fixmap(FIX_EFI_IO_MAP_FIRST_PAGE - pages_mapped,
> + offset, PAGE_KERNEL_EXEC);

you've changed it from nocache-noexec to cached-exec. I suspect that's
what we want - except if an early EFI area can be non-prefetchable
device memory. Can that ever happen? Would you like to have
PAGE_KERNEL_NOCACHE_EXEC perhaps? I implemented that yesterday but did
not commit it yet. (see the patch below)

Ingo

----------------->
Subject: x86: add PAGE_KERNEL_EXEC_NOCACHE
From: Ingo Molnar <mingo@elte.hu>

add PAGE_KERNEL_EXEC_NOCACHE.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
include/asm-x86/pgtable.h | 2 ++
1 file changed, 2 insertions(+)

Index: linux-x86.q/include/asm-x86/pgtable.h
===================================================================
--- linux-x86.q.orig/include/asm-x86/pgtable.h
+++ linux-x86.q/include/asm-x86/pgtable.h
@@ -79,6 +79,7 @@ extern pteval_t __PAGE_KERNEL, __PAGE_KE

#define __PAGE_KERNEL_RO (__PAGE_KERNEL & ~_PAGE_RW)
#define __PAGE_KERNEL_RX (__PAGE_KERNEL_EXEC & ~_PAGE_RW)
+#define __PAGE_KERNEL_EXEC_NOCACHE (__PAGE_KERNEL_EXEC | _PAGE_PCD | _PAGE_PWT)
#define __PAGE_KERNEL_NOCACHE (__PAGE_KERNEL | _PAGE_PCD | _PAGE_PWT)
#define __PAGE_KERNEL_VSYSCALL (__PAGE_KERNEL_RX | _PAGE_USER)
#define __PAGE_KERNEL_VSYSCALL_NOCACHE (__PAGE_KERNEL_VSYSCALL | _PAGE_PCD | _PAGE_PWT)
@@ -96,6 +97,7 @@ extern pteval_t __PAGE_KERNEL, __PAGE_KE
#define PAGE_KERNEL_EXEC MAKE_GLOBAL(__PAGE_KERNEL_EXEC)
#define PAGE_KERNEL_RX MAKE_GLOBAL(__PAGE_KERNEL_RX)
#define PAGE_KERNEL_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
+#define PAGE_KERNEL_EXEC_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_EXEC_NOCACHE)
#define PAGE_KERNEL_LARGE MAKE_GLOBAL(__PAGE_KERNEL_LARGE)
#define PAGE_KERNEL_LARGE_EXEC MAKE_GLOBAL(__PAGE_KERNEL_LARGE_EXEC)
#define PAGE_KERNEL_VSYSCALL MAKE_GLOBAL(__PAGE_KERNEL_VSYSCALL)

\
 
 \ /
  Last update: 2008-01-25 10:19    [W:0.065 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site