From 63550530d98db6e9c30dc96a3ea08411b873b23e Mon Sep 17 00:00:00 2001 From: Samuel Thibault Date: Thu, 9 Feb 2023 19:58:43 +0100 Subject: [PATCH] hurd: Fix unwinding over INTR_MSG_TRAP We used to use .cfi_adjust_cfa_offset around %esp manipulation asm instructions to fix unwinding, but when building glibc with -fno-omit-frame-pointer this is bogus since in that case %ebp is the CFA and does not move. Instead, let's force -fno-omit-frame-pointer when building intr-msg.c so that %ebp can always be used and no .cfi_adjust_cfa_offset is needed. --- hurd/Makefile | 3 +++ sysdeps/mach/hurd/i386/intr-msg.h | 13 ------------- 2 files changed, 3 insertions(+), 13 deletions(-) diff --git a/hurd/Makefile b/hurd/Makefile index 77cb16cdf7..7c34e9ad0d 100644 --- a/hurd/Makefile +++ b/hurd/Makefile @@ -89,6 +89,9 @@ generated += $(inlines:=.c) # Avoid ssp before TLS is initialized. CFLAGS-hurdstartup.o = $(no-stack-protector) CFLAGS-RPC_exec_startup_get_info.o = $(no-stack-protector) + +# Make it simpler to unwind over INTR_MSG_TRAP +CFLAGS-intr-msg.o = -fno-omit-frame-pointer # Make generated headers compatible with all support standards migheaderpipe := | sed -e 's/\/__ino64_t/' -e 's/\/__loff_t/' diff --git a/sysdeps/mach/hurd/i386/intr-msg.h b/sysdeps/mach/hurd/i386/intr-msg.h index 58f2f37c17..29cb4620da 100644 --- a/sysdeps/mach/hurd/i386/intr-msg.h +++ b/sysdeps/mach/hurd/i386/intr-msg.h @@ -41,21 +41,13 @@ "_hurd_intr_rpc_msg_do:" \ /* Ok, push the mach_msg_trap arguments. */ \ " pushl 24(%4)\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl %2\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl 16(%4)\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl 12(%4)\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl 8(%4)\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl %1\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl (%4)\n" \ - " .cfi_adjust_cfa_offset 4\n" \ " pushl $0\n" \ - " .cfi_adjust_cfa_offset 4\n" \ /* TODO: remove this ecx kludge, we don't need it any more */ \ " movl %%esp, %%ecx\n" \ "_hurd_intr_rpc_msg_cx_sp: movl $-25, %%eax\n" \ @@ -63,15 +55,10 @@ "_hurd_intr_rpc_msg_in_trap:" \ /* Ok, clean the arguments and update OPTION and TIMEOUT. */ \ " addl $8, %%esp\n" \ - " .cfi_adjust_cfa_offset -8\n" \ " popl %1\n" \ - " .cfi_adjust_cfa_offset -4\n" \ " addl $12, %%esp\n" \ - " .cfi_adjust_cfa_offset -12\n" \ " popl %2\n" \ - " .cfi_adjust_cfa_offset -4\n" \ " addl $4, %%esp\n" \ - " .cfi_adjust_cfa_offset -4\n" \ "_hurd_intr_rpc_msg_sp_restored:" \ : "=a" (err), "+r" (option), "+r" (timeout), "=m" (*intr_port_p) \ : "r" (&msg), "m" (*cancel_p), "i" (EINTR) \ -- 2.43.5