Re: [PATCH v7 1/3] x86/mm: Adapt MODULES_END based on Fixmap section size

From
Ingo Molnar <mingo@kernel.org>
Date
2017-03-16 08:10:25
Also in
kvm, linux-efi, linux-mm, lkml
Reply to
Thomas Garnier, 2017-03-14
* Thomas Garnier [off-list ref] wrote:
This patch aligns MODULES_END to the beginning of the Fixmap section.
It optimizes the space available for both sections. The address is
pre-computed based on the number of pages required by the Fixmap
section.

It will allow GDT remapping in the Fixmap section. The current
MODULES_END static address does not provide enough space for the kernel
to support a large number of processors.

Signed-off-by: Thomas Garnier <redacted>
---
Based on next-20170308
---
 Documentation/x86/x86_64/mm.txt         | 5 ++++-
 arch/x86/include/asm/pgtable_64_types.h | 3 ++-
 arch/x86/kernel/module.c                | 1 +
 arch/x86/mm/dump_pagetables.c           | 1 +
 arch/x86/mm/kasan_init_64.c             | 1 +
 mm/vmalloc.c                            | 1 +
quoted hunk ↗ jump to hunk
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -35,6 +35,7 @@
 #include <linux/uaccess.h>
 #include <asm/tlbflush.h>
 #include <asm/shmparam.h>
+#include <asm/fixmap.h>
 
 #include "internal.h"
Note that asm/fixmap.h is an x86-ism that isn't present in many other 
architectures, so this hunk will break the build.

To make progress with these patches I've fixed it up with an ugly #ifdef 
CONFIG_X86, but it needs a real solution instead before this can be pushed 
upstream.

Thanks,

	Ingo

=====================>
 mm/vmalloc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index dabea6a29fad..b7d2a23349f4 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -35,7 +35,10 @@
 #include <linux/uaccess.h>
 #include <asm/tlbflush.h>
 #include <asm/shmparam.h>
-#include <asm/fixmap.h>
+
+#ifdef CONFIG_X86
+# include <asm/fixmap.h>
+#endif
 
 #include "internal.h"
 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
Thread (9 messages) 9 messages, 4 authors, last reply 2017-03-17
Keyboard shortcuts
hback out one level
jnext message in thread / next series-diff position
kprevious message in thread / previous series-diff position
ldrill in
Escclose help / fold thread tree
?toggle this help