ARM: verify size of zImage
PATCH 1/1 ARM: verify size of zImage
The linker can sometimes add additional sections to the zImage ELF file which results in the zImage binary being larger than expected. This causes appended DT blobs to fail.
Verify that the zImage binary is the expected size, and fail the build if this is not the case.
---
As this patch is different, I've dropped Matthias' tested-by. I'd appreciate a replacement, thanks. Also, I seem to remember that Ard's toolchain was giving issues - maybe this alternative will finally resolve them.
arch/arm/boot/compressed/vmlinux.lds.S | 7 +++++++ 1 file changed, 7 insertions(+)
arch/arm/boot/compressed/vmlinux.lds.S +7 -0
@@ -101,6 +101,12 @@ SECTIONS * this symbol allows further debug in the near future. */ .image_end (NOLOAD) : { + /* + * EFI requires that the image is aligned to 512 bytes, and appended + * DTB requires that we know where the end of the image is. Ensure + * that both are satisfied by ensuring that there are no additional + * sections emitted into the decompressor image. + */ _edata_real = .; }
@@ -128,3 +134,4 @@ SECTIONS .stab.indexstr 0 : { *(.stab.indexstr) } .comment 0 : { *(.comment) } } +ASSERT(_edata_real == _edata, "error: zImage file size is incorrect");
Signature · 1 line
2.7.4
PATCH 1/1 ARM: verify size of zImage
(+ Gregory)
Quoted 7 lines · Russell King
The linker can sometimes add additional sections to the zImage ELF file which results in the zImage binary being larger than expected. This causes appended DT blobs to fail.
Verify that the zImage binary is the expected size, and fail the build if this is not the case.
Quoted 7 lines
Signed-off-by Russell King <[email protected]>---
As this patch is different, I've dropped Matthias' tested-by. I'd appreciate a replacement, thanks. Also, I seem to remember that Ard's toolchain was giving issues - maybe this alternative will finally resolve them.
$ nm arch/arm/boot/compressed/vmlinux |grep _edata 007b8200 D _edata 007b8200 D _edata_real
although I don't remember seeing this fail. It think it may have been Gregory who was having these issues?
Quoted 28 lines
arch/arm/boot/compressed/vmlinux.lds.S | 7 +++++++ 1 file changed, 7 insertions(+)arch/arm/boot/compressed/vmlinux.lds.S +7
-1@@ -101,6 +101,12 @@ SECTIONS * this symbol allows further debug in the near future. */ .image_end (NOLOAD) : { + /* + * EFI requires that the image is aligned to 512 bytes, and appended + * DTB requires that we know where the end of the image is. Ensure + * that both are satisfied by ensuring that there are no additional + * sections emitted into the decompressor image. + */ _edata_real = .; }@@ -128,3 +134,4 @@ SECTIONS .stab.indexstr 0 : { *(.stab.indexstr) } .comment 0 : { *(.comment) } } +ASSERT(_edata_real == _edata, "error: zImage file size is incorrect"); --2.7.4
Russell King - ARM Linux
maintainerPATCH 1/1 ARM: verify size of zImage
Quoted 18 lines · Ard Biesheuvel
(+ Gregory)
Quoted 7 lines · Russell King
The linker can sometimes add additional sections to the zImage ELF file which results in the zImage binary being larger than expected. This causes appended DT blobs to fail.
Verify that the zImage binary is the expected size, and fail the build if this is not the case.
Quoted 7 lines
Signed-off-by Russell King <[email protected]>---
As this patch is different, I've dropped Matthias' tested-by. I'd appreciate a replacement, thanks. Also, I seem to remember that Ard's toolchain was giving issues - maybe this alternative will finally resolve them.
Quoted 8 lines
$ nm arch/arm/boot/compressed/vmlinux |grep _edata 007b8200 D _edata 007b8200 D _edata_realTested-by Ard Biesheuvel <[email protected]>although I don't remember seeing this fail. It think it may have been Gregory who was having these issues?
The failing case was with a few ld versions when we had:
ASSERT(. == _edata, "error: zImage file size is incorrect");
in place of the _edata_real assignment. Yet, those very same linkers have shown that they set _edata_real to the same value as _edata.
I forget who had the problem, sorry.
Signature · 3 lines
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up According to speedtest.net: 8.21Mbps down 510kbps up
PATCH 1/1 ARM: verify size of zImage
In reply to Ard BiesheuvelHi Ard,
Quoted 18 lines · Ard Biesheuvel
(+ Gregory)
Quoted 7 lines · Russell King
The linker can sometimes add additional sections to the zImage ELF file which results in the zImage binary being larger than expected. This causes appended DT blobs to fail.
Verify that the zImage binary is the expected size, and fail the build if this is not the case.
Quoted 7 lines
Signed-off-by Russell King <[email protected]>---
As this patch is different, I've dropped Matthias' tested-by. I'd appreciate a replacement, thanks. Also, I seem to remember that Ard's toolchain was giving issues - maybe this alternative will finally resolve them.
Quoted 8 lines
$ nm arch/arm/boot/compressed/vmlinux |grep _edata 007b8200 D _edata 007b8200 D _edata_realTested-by Ard Biesheuvel <[email protected]>although I don't remember seeing this fail. It think it may have been Gregory who was having these issues?
Thanks to remember me, I finally find time to test it, and with my setup I didn't have anymore issue while building it for a dtb append zImage for Armada XP:
Gregory
Quoted 31 lines
Quoted 31 lines
arch/arm/boot/compressed/vmlinux.lds.S | 7 +++++++ 1 file changed, 7 insertions(+)arch/arm/boot/compressed/vmlinux.lds.S +7
-1@@ -101,6 +101,12 @@ SECTIONS * this symbol allows further debug in the near future. */ .image_end (NOLOAD) : { + /* + * EFI requires that the image is aligned to 512 bytes, and appended + * DTB requires that we know where the end of the image is. Ensure + * that both are satisfied by ensuring that there are no additional + * sections emitted into the decompressor image. + */ _edata_real = .; }@@ -128,3 +134,4 @@ SECTIONS .stab.indexstr 0 : { *(.stab.indexstr) } .comment 0 : { *(.comment) } } +ASSERT(_edata_real == _edata, "error: zImage file size is incorrect"); --2.7.4
Signature · 4 lines
Gregory Clement, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com
PATCH 1/1 ARM: verify size of zImage
Quoted 28 lines · Gregory CLEMENT
Hi Ard,
Quoted 24 lines · Ard Biesheuvel
(+ Gregory)
Quoted 7 lines · Russell King
The linker can sometimes add additional sections to the zImage ELF file which results in the zImage binary being larger than expected. This causes appended DT blobs to fail.
Verify that the zImage binary is the expected size, and fail the build if this is not the case.
Quoted 7 lines
Signed-off-by Russell King <[email protected]>---
As this patch is different, I've dropped Matthias' tested-by. I'd appreciate a replacement, thanks. Also, I seem to remember that Ard's toolchain was giving issues - maybe this alternative will finally resolve them.$ nm arch/arm/boot/compressed/vmlinux |grep _edata 007b8200 D _edata 007b8200 D _edata_realTested-by Ard Biesheuvel <[email protected]>
Quoted 9 lines
Quoted 2 lines
although I don't remember seeing this fail. It think it may have been Gregory who was having these issues?
Thanks to remember me, I finally find time to test it, and with my setup I didn't have anymore issue while building it for a dtb append zImage for Armada XP:
Tested-by Gregory CLEMENT <[email protected]>
Thanks for confirming.