ARM: decompress: Use /memreserve/ DTS nodes when validating memory
PATCH 1/1 ARM: decompress: Use /memreserve/ DTS nodes when validating memory
If the bootloader needs the start of memory to be preserved, for example because it dropped the Trusted Firmware blob there, this chunk of memory shouldn't be used by the kernel.
To avoid adding yet another SoC-specific text offset to arch/arm/Makefile, this patch allows for a /memreserve/ entry in the DTS to mark off the memory chunk instead.
--- arch/arm/boot/compressed/fdt_check_mem_start.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)
arch/arm/boot/compressed/fdt_check_mem_start.c +14 -1
@@ -64,7 +64,7 @@ uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)uint32_t addr_cells, size_cells, base;uint32_t fdt_mem_start =0xffffffff ;const fdt32_t *reg, *endp; -uint64_t size, end; +uint64_t rsvaddr, size, end;const char *type;int offset, len;
@@ -74,6 +74,19 @@ uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)if (fdt_magic (fdt) !=FDT_MAGIC )return mem_start; +for (offset =fdt_off_mem_rsvmap (fdt); ; offset +=16 ) { + rsvaddr =get_val (fdt + offset,8 ); + size =get_val (fdt + offset +8 ,8 ); + +if (!rsvaddr && !size) +break ; + + end = rsvaddr + size; +if (mem_start >= rsvaddr && mem_start <= end) +/* Relocate past reserved block */ + mem_start =round_up (end,SZ_2M ); + } +/* There may be multiple cells on LPAE platforms */ addr_cells =get_cells (fdt,"#address-cells" ); size_cells =get_cells (fdt,"#size-cells" );
Signature · 1 line
2.25.1
Hoi Bert,
Quoted 9 lines · Bert Vermeulen
If the bootloader needs the start of memory to be preserved, for example because it dropped the Trusted Firmware blob there, this chunk of memory shouldn't be used by the kernel.
To avoid adding yet another SoC-specific text offset to
arch/arm/Makefile, this patch allows for a /memreserve/ entry in the DTS to mark off the memory chunk instead.Signed-off-by Bert Vermeulen <[email protected]>
Thanks for your patch!
Quoted 12 lines
arch/arm/boot/compressed/fdt_check_mem_start.c +1
-1@@ -64,7 +64,7 @@ uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)uint32_t addr_cells, size_cells, base;uint32_t fdt_mem_start =0xffffffff ;const fdt32_t *reg, *endp; -uint64_t size, end; +uint64_t rsvaddr, size, end;const char *type;int offset, len;
arch/arm/boot/compressed/fdt_check_mem_start.c uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt) · line 79
Quoted 6 lines
arch/arm/boot/compressed/fdt_check_mem_start.c +3
-0@@ -74,6 +74,19 @@ uint32_t fdt_check_mem_start(uint32_t mem_start, const void *fdt)if (fdt_magic (fdt) !=FDT_MAGIC )return mem_start; +for (offset =fdt_off_mem_rsvmap (fdt); ; offset +=16 ) { + rsvaddr =get_val (fdt + offset,8 ); + size =get_val (fdt + offset +8 ,8 );
The last parameter of get_val() is the number of cells, not the number of bytes. Hence it should be 2 for the 64-bit values in the memory reservation block.
The rest looks good to me.
Gr{oetje,eeting}s,
Geert
Signature · 5 lines
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected] In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds