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author | Tony Lindgren <tony@atomide.com> | 2018-03-21 08:16:29 -0700 |
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committer | Tony Lindgren <tony@atomide.com> | 2018-03-21 08:16:29 -0700 |
commit | eb85a355c3afd9379f5953cfe2df73632d14c884 (patch) | |
tree | dae7f3fcc93347f43fb37b3f16e710568d59bd27 | |
parent | ba6887836178d43b3665b9da075c2c5dfe1d207c (diff) | |
download | blackbird-obmc-linux-eb85a355c3afd9379f5953cfe2df73632d14c884.tar.gz blackbird-obmc-linux-eb85a355c3afd9379f5953cfe2df73632d14c884.zip |
ARM: OMAP: Fix SRAM W+X mapping
We are still using custom SRAM code for some SoCs and are not marking
the PM code mapped to SRAM as read-only and executable after we're
done. With CONFIG_DEBUG_WX=y, we will get "Found insecure W+X mapping
at address" warning.
Let's fix this issue the same way as commit 728bbe75c82f ("misc: sram:
Introduce support code for protect-exec sram type") is doing for
drivers/misc/sram-exec.c.
On omap3, we need to restore SRAM when returning from off mode after
idle, so init time configuration is not enough.
And as we no longer have users for omap_sram_push_address() we can
make it static while at it.
Note that eventually we should be using sram-exec.c for all SoCs.
Cc: stable@vger.kernel.org # v4.12+
Cc: Dave Gerlach <d-gerlach@ti.com>
Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
-rw-r--r-- | arch/arm/plat-omap/include/plat/sram.h | 11 | ||||
-rw-r--r-- | arch/arm/plat-omap/sram.c | 36 |
2 files changed, 36 insertions, 11 deletions
diff --git a/arch/arm/plat-omap/include/plat/sram.h b/arch/arm/plat-omap/include/plat/sram.h index fb061cf0d736..30a07730807a 100644 --- a/arch/arm/plat-omap/include/plat/sram.h +++ b/arch/arm/plat-omap/include/plat/sram.h @@ -5,13 +5,4 @@ void omap_map_sram(unsigned long start, unsigned long size, unsigned long skip, int cached); void omap_sram_reset(void); -extern void *omap_sram_push_address(unsigned long size); - -/* Macro to push a function to the internal SRAM, using the fncpy API */ -#define omap_sram_push(funcp, size) ({ \ - typeof(&(funcp)) _res = NULL; \ - void *_sram_address = omap_sram_push_address(size); \ - if (_sram_address) \ - _res = fncpy(_sram_address, &(funcp), size); \ - _res; \ -}) +extern void *omap_sram_push(void *funcp, unsigned long size); diff --git a/arch/arm/plat-omap/sram.c b/arch/arm/plat-omap/sram.c index a5bc92d7e476..921840acf65c 100644 --- a/arch/arm/plat-omap/sram.c +++ b/arch/arm/plat-omap/sram.c @@ -23,6 +23,7 @@ #include <asm/fncpy.h> #include <asm/tlb.h> #include <asm/cacheflush.h> +#include <asm/set_memory.h> #include <asm/mach/map.h> @@ -42,7 +43,7 @@ static void __iomem *omap_sram_ceil; * Note that fncpy requires the returned address to be aligned * to an 8-byte boundary. */ -void *omap_sram_push_address(unsigned long size) +static void *omap_sram_push_address(unsigned long size) { unsigned long available, new_ceil = (unsigned long)omap_sram_ceil; @@ -60,6 +61,30 @@ void *omap_sram_push_address(unsigned long size) return (void *)omap_sram_ceil; } +void *omap_sram_push(void *funcp, unsigned long size) +{ + void *sram; + unsigned long base; + int pages; + void *dst = NULL; + + sram = omap_sram_push_address(size); + if (!sram) + return NULL; + + base = (unsigned long)sram & PAGE_MASK; + pages = PAGE_ALIGN(size) / PAGE_SIZE; + + set_memory_rw(base, pages); + + dst = fncpy(sram, funcp, size); + + set_memory_ro(base, pages); + set_memory_x(base, pages); + + return dst; +} + /* * The SRAM context is lost during off-idle and stack * needs to be reset. @@ -75,6 +100,9 @@ void omap_sram_reset(void) void __init omap_map_sram(unsigned long start, unsigned long size, unsigned long skip, int cached) { + unsigned long base; + int pages; + if (size == 0) return; @@ -95,4 +123,10 @@ void __init omap_map_sram(unsigned long start, unsigned long size, */ memset_io(omap_sram_base + omap_sram_skip, 0, omap_sram_size - omap_sram_skip); + + base = (unsigned long)omap_sram_base; + pages = PAGE_ALIGN(omap_sram_size) / PAGE_SIZE; + + set_memory_ro(base, pages); + set_memory_x(base, pages); } |