Patchwork [v11,01/14] uaccess: add untagged_addr definition for other arches

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Submitter Andrey Konovalov
Date March 15, 2019, 7:51 p.m.
Message ID <bee403f76b40f37c6790d144a4142f293e0a7d9f.1552679409.git.andreyknvl@google.com>
Download mbox | patch
Permalink /patch/749927/
State New
Headers show

Comments

Andrey Konovalov - March 15, 2019, 7:51 p.m.
To allow arm64 syscalls to accept tagged pointers from userspace, we must
untag them when they are passed to the kernel. Since untagging is done in
generic parts of the kernel, the untagged_addr macro needs to be defined
for all architectures.

Define it as a noop for architectures other than arm64.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 include/linux/mm.h | 4 ++++
 1 file changed, 4 insertions(+)

Patch

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 76769749b5a5..4d674518d392 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -99,6 +99,10 @@  extern int mmap_rnd_compat_bits __read_mostly;
 #include <asm/pgtable.h>
 #include <asm/processor.h>
 
+#ifndef untagged_addr
+#define untagged_addr(addr) (addr)
+#endif
+
 #ifndef __pa_symbol
 #define __pa_symbol(x)  __pa(RELOC_HIDE((unsigned long)(x), 0))
 #endif