diff options
| author | Bernd Schmidt <bernds_cb1@t-online.de> | 2008-04-23 21:06:15 +0200 |
|---|---|---|
| committer | Bryan Wu <cooloney@kernel.org> | 2008-04-23 21:06:15 +0200 |
| commit | d5adb029efad3c51db376d620319abe65d1efc21 (patch) | |
| tree | 660caff4c28e904f00a040c0ed4a17d5010c6f20 | |
| parent | [Blackfin] arch: support the reserved memory region in the MPU code (diff) | |
| download | linux-d5adb029efad3c51db376d620319abe65d1efc21.tar.xz linux-d5adb029efad3c51db376d620319abe65d1efc21.zip | |
[Blackfin] arch: This allows XIP to work with FD-PIC.
Previously, init failed to do anything meaningful;
it turns out that the reason is that FD-PIC has a readonly data
section which can be located in the XIP filesystem, and various address checks
in the kernel reject such addresses for syscall arguments. Hence, init's
execve ("/bin/sh", ...)
failed with error code EFAULT.
There's room for improvement here: in case people want to have filesystems
on flash rather than in main memory, _access_ok should be modified to
allow this.
This bug fix is also dedicated to Michael Hennerich.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to '')
| -rw-r--r-- | arch/blackfin/kernel/process.c | 6 | ||||
| -rw-r--r-- | include/asm-blackfin/processor.h | 5 |
2 files changed, 9 insertions, 2 deletions
diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c index fb94cbeafad6..be9fdd00d7cb 100644 --- a/arch/blackfin/kernel/process.c +++ b/arch/blackfin/kernel/process.c @@ -324,6 +324,12 @@ int _access_ok(unsigned long addr, unsigned long size) return 1; if (addr >= memory_mtd_end && (addr + size) <= physical_mem_end) return 1; + +#ifdef CONFIG_ROMFS_MTD_FS + /* For XIP, allow user space to use pointers within the ROMFS. */ + if (addr >= memory_mtd_start && (addr + size) <= memory_mtd_end) + return 1; +#endif #else if (addr >= memory_start && (addr + size) <= physical_mem_end) return 1; diff --git a/include/asm-blackfin/processor.h b/include/asm-blackfin/processor.h index 1033e5c76011..1c0040724612 100644 --- a/include/asm-blackfin/processor.h +++ b/include/asm-blackfin/processor.h @@ -26,9 +26,10 @@ static inline void wrusp(unsigned long usp) /* * User space process size: 1st byte beyond user address space. + * Fairly meaningless on nommu. Parts of user programs can be scattered + * in a lot of places, so just disable this by setting it to 0xFFFFFFFF. */ -extern unsigned long memory_end; -#define TASK_SIZE (memory_end) +#define TASK_SIZE 0xFFFFFFFF #ifdef __KERNEL__ #define STACK_TOP TASK_SIZE |