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@@ -0,0 +1,36 @@
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+From: Matthias Schiffer <mschiffer@universe-factory.net>
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+Date: Sun, 28 Feb 2016 04:49:51 +0100
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+Subject: ar71xx/lzma-loader: fix O32 ABI conformance
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+
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+According to the calling convention of the o32 ABI the caller
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+function must reserve stack space for $a0-$a3 registers in case
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+the callee needs to save its arguments.
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+
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+The assembly code of the loader does not reserve stack space for
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+these registers thus when the 'loader_main' function needs to save
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+its arguments, those will be stored in the 'workspace' area instead
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+of the stack.
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+
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+Because the workspace area is also used by other part of the code, the
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+saved register values gets overwritten and this often leads to failed
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+kernel boots.
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+
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+Fix the code to reserve stack space for the registers to avoid this
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+error.
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+
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+Backport of r48279
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+
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+diff --git a/target/linux/ar71xx/image/lzma-loader/src/head.S b/target/linux/ar71xx/image/lzma-loader/src/head.S
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+index 543996a..47a7c9b 100644
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+--- a/target/linux/ar71xx/image/lzma-loader/src/head.S
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++++ b/target/linux/ar71xx/image/lzma-loader/src/head.S
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+@@ -109,6 +109,9 @@ __bss_check:
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+ /* Setup new "C" stack */
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+ la sp, _stack
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+
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++ /* reserve stack space for a0-a3 registers */
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++ subu sp, 16
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++
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+ /* jump to the decompressor routine */
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+ la t0, loader_main
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+ jr t0
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