Richard Henderson wrote:
> So you also need a
>
> 0x85 0x04 DW_CFA_offset %ebp -16
> [...]
Updated patch attached.
-- --------------. ,-. 444 Castro Street Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA Red Hat `--' drepper at redhat.com `---------------------------
--- linux-2.5/arch/i386/kernel/sysenter.c-eh 2003-04-13 15:32:51.000000000 -0700 +++ linux-2.5/arch/i386/kernel/sysenter.c 2003-04-13 15:30:22.000000000 -0700 @@ -12,6 +12,7 @@ #include <linux/sched.h> #include <linux/gfp.h> #include <linux/string.h> +#include <linux/elf.h> #include <asm/cpufeature.h> #include <asm/msr.h> @@ -52,11 +53,47 @@ void enable_sep_cpu(void *info) static int __init sysenter_setup(void) { - static const char int80[] = { + static const char __initdata int80[] = { 0xcd, 0x80, /* int $0x80 */ 0xc3 /* ret */ }; - static const char sysent[] = { + /* Unwind information for the int80 code. Keep track of + where the return address is stored. */ + static const char __initdata int80_eh_frame[] = { + /* First the Common Information Entry (CIE): */ + 0x14, 0x00, 0x00, 0x00, /* Length of the CIE */ + 0x00, 0x00, 0x00, 0x00, /* CIE Identifier Tag */ + 0x01, /* CIE Version */ + 'z', 'R', 0x00, /* CIE Augmentation */ + 0x01, /* CIE Code Alignment Factor */ + 0x7c, /* CIE Data Alignment Factor */ + 0x08, /* CIE RA Column */ + 0x01, /* Augmentation size */ + 0x1b, /* FDE Encoding (pcrel sdata4) */ + 0x0c, /* DW_CFA_def_cfa */ + 0x04, + 0x04, + 0x88, /* DW_CFA_offset, column 0x8 */ + 0x01, + 0x00, /* padding */ + 0x00, + /* Now the FDE which contains the instructions for the frame. */ + 0x0a, 0x00, 0x00, 0x00, /* FDE Length */ + 0x1c, 0x00, 0x00, 0x00, /* FDE CIE offset */ + /* The PC-relative offset to the beginning of the code this + FDE covers. The computation below assumes that the offset + can be represented in one byte. Change if this is not true + anymore. The offset from the beginning of the .eh_frame + is represented by EH_FRAME_OFFSET. The word with the offset + starts at byte 0x20 of the .eh_frame. */ + 0x100 - (EH_FRAME_OFFSET + 0x20), + 0xff, 0xff, 0xff, /* FDE initial location */ + 3, /* FDE address range */ + 0x00 /* Augmentation size */ + /* The code does not change the stack pointer. We need not + record any operations. */ + }; + static const char __initdata sysent[] = { 0x51, /* push %ecx */ 0x52, /* push %edx */ 0x55, /* push %ebp */ @@ -76,13 +113,71 @@ static int __init sysenter_setup(void) 0x59, /* pop %ecx */ 0xc3 /* ret */ }; - static const char sigreturn[] = { + /* Unwind information for the sysenter code. Keep track of + where the return address is stored. */ + static const char __initdata sysent_eh_frame[] = { + /* First the Common Information Entry (CIE): */ + 0x14, 0x00, 0x00, 0x00, /* Length of the CIE */ + 0x00, 0x00, 0x00, 0x00, /* CIE Identifier Tag */ + 0x01, /* CIE Version */ + 'z', 'R', 0x00, /* CIE Augmentation */ + 0x01, /* CIE Code Alignment Factor */ + 0x7c, /* CIE Data Alignment Factor */ + 0x08, /* CIE RA Column */ + 0x01, /* Augmentation size */ + 0x1b, /* FDE Encoding (pcrel sdata4) */ + 0x0c, /* DW_CFA_def_cfa */ + 0x04, + 0x04, + 0x88, /* DW_CFA_offset, column 0x8 */ + 0x01, + 0x00, /* padding */ + 0x00, + /* Now the FDE which contains the instructions for the frame. */ + 0x22, 0x00, 0x00, 0x00, /* FDE Length */ + 0x1c, 0x00, 0x00, 0x00, /* FDE CIE offset */ + /* The PC-relative offset to the beginning of the code this + FDE covers. The computation below assumes that the offset + can be represented in one byte. Change if this is not true + anymore. The offset from the beginning of the .eh_frame + is represented by EH_FRAME_OFFSET. The word with the offset + starts at byte 0x20 of the .eh_frame. */ + 0x100 - (EH_FRAME_OFFSET + 0x20), + 0xff, 0xff, 0xff, /* FDE initial location */ + 0x14, 0x00, 0x00, 0x00, /* FDE address range */ + 0x00, /* Augmentation size */ + /* What follows are the instructions for the table generation. + We have to record all changes of the stack pointer and + callee-saved registers. */ + 0x41, /* DW_CFA_advance_loc+1, push %ecx */ + 0x0e, /* DW_CFA_def_cfa_offset */ + 0x08, /* RA at offset 8 now */ + 0x41, /* DW_CFA_advance_loc+1, push %edx */ + 0x0e, /* DW_CFA_def_cfa_offset */ + 0x0c, /* RA at offset 12 now */ + 0x41, /* DW_CFA_advance_loc+1, push %ebp */ + 0x0e, /* DW_CFA_def_cfa_offset */ + 0x10, /* RA at offset 16 now */ + 0x85, 0x04, /* DW_CFA_offset %ebp -16 */ + /* Finally the epilogue. */ + 0x4e, /* DW_CFA_advance_loc+14, pop %ebx */ + 0x0e, /* DW_CFA_def_cfa_offset */ + 0x12, /* RA at offset 12 now */ + 0xc5, /* DW_CFA_restore %ebp */ + 0x41, /* DW_CFA_advance_loc+1, pop %edx */ + 0x0e, /* DW_CFA_def_cfa_offset */ + 0x08, /* RA at offset 8 now */ + 0x41, /* DW_CFA_advance_loc+1, pop %ecx */ + 0x0e, /* DW_CFA_def_cfa_offset */ + 0x04 /* RA at offset 4 now */ + }; + static const char __initdata sigreturn[] = { /* 32: sigreturn point */ 0x58, /* popl %eax */ 0xb8, __NR_sigreturn, 0, 0, 0, /* movl $__NR_sigreturn, %eax */ 0xcd, 0x80, /* int $0x80 */ }; - static const char rt_sigreturn[] = { + static const char __initdata rt_sigreturn[] = { /* 64: rt_sigreturn point */ 0xb8, __NR_rt_sigreturn, 0, 0, 0, /* movl $__NR_rt_sigreturn, %eax */ 0xcd, 0x80, /* int $0x80 */ @@ -93,10 +188,14 @@ static int __init sysenter_setup(void) memcpy((void *) page, int80, sizeof(int80)); memcpy((void *)(page + 32), sigreturn, sizeof(sigreturn)); memcpy((void *)(page + 64), rt_sigreturn, sizeof(rt_sigreturn)); + memcpy((void *)(page + EH_FRAME_OFFSET), int80_eh_frame, + sizeof(int80_eh_frame)); if (!boot_cpu_has(X86_FEATURE_SEP)) return 0; memcpy((void *) page, sysent, sizeof(sysent)); + memcpy((void *)(page + EH_FRAME_OFFSET), sysent_eh_frame, + sizeof(sysent_eh_frame)); on_each_cpu(enable_sep_cpu, NULL, 1, 1); return 0; } --- linux-2.5/include/asm-i386/elf.h-eh 2003-04-13 15:31:35.000000000 -0700 +++ linux-2.5/include/asm-i386/elf.h 2003-04-13 14:47:04.000000000 -0700 @@ -100,7 +100,8 @@ typedef struct user_fxsr_struct elf_fpxr * Architecture-neutral AT_ values in 0-17, leave some room * for more of them, start the x86-specific ones at 32. */ -#define AT_SYSINFO 32 +#define AT_SYSINFO 32 +#define AT_SYSINFO_EH_FRAME 33 #ifdef __KERNEL__ #define SET_PERSONALITY(ex, ibcs2) set_personality((ibcs2)?PER_SVR4:PER_LINUX) @@ -118,9 +119,15 @@ extern void dump_smp_unlazy_fpu(void); #define ELF_CORE_SYNC dump_smp_unlazy_fpu #endif -#define ARCH_DLINFO \ -do { \ - NEW_AUX_ENT(AT_SYSINFO, 0xffffe000); \ +/* Offset from the beginning of the page where the .eh_frame information + for the code in the vsyscall page starts. */ +#define EH_FRAME_OFFSET 96 + +#define ARCH_DLINFO \ +do { \ + NEW_AUX_ENT(AT_SYSINFO, 0xffffe000); \ + NEW_AUX_ENT(AT_SYSINFO_EH_FRAME, \ + 0xffffe000 + EH_FRAME_OFFSET); \ } while (0) #endif
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This archive was generated by hypermail 2b29 : Tue Apr 15 2003 - 22:00:29 EST