From e9e770dfd6224a5ff7932b6115a35005dce7be29 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Tue, 22 Sep 2015 20:51:59 +0000 Subject: have sh/fdpic entry point set fdpic personality if needed the entry point code supports being loaded by a loader which is not fdpic-aware (in practice, either kernel with mmu or qemu without fdpic support). this mostly just works, but signal handling will wrongly use a function descriptor address as a code address if the personality is not adjusted to fdpic. ideally this code could be placed with sigaction so that it's not needed except if/when a signal handler is installed. however, personality is incorrectly maintained per-thread by the kernel, rather than per-process, so it's necessary to correct the personality before any threads are started. also, in order to skip the personality syscall when an fdpic-aware loader is used, we need to be able to detect how the program was loaded, and this information is only readily available at the entry point. --- arch/sh/crt_arch.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/sh/crt_arch.h b/arch/sh/crt_arch.h index d63ce0d1..948bcb79 100644 --- a/arch/sh/crt_arch.h +++ b/arch/sh/crt_arch.h @@ -4,6 +4,18 @@ __asm__( ".text \n" ".global " START " \n" START ": \n" +" tst r8, r8 \n" +" bf 1f \n" +" mov #68, r3 \n" +" add r3, r3 \n" +" mov #8, r4 \n" +" swap.w r4, r4 \n" +" trapa #31 \n" +" nop \n" +" nop \n" +" nop \n" +" nop \n" +"1: nop \n" #ifndef SHARED " mov r8, r4 \n" " mova 1f, r0 \n" -- cgit v1.2.3-70-g09d2