Re: [Qemu-devel] [PATCH] qemu-i386 segfaults running hello world.
On Monday 02 July 2007 11:02:49 Alexander Graf wrote: Hi, this is the patch we are currently using to build qemu-0.9.0. Does this work for you? Alex Let's see... -/* ld script to make i386 Linux kernel - * Written by Martin Mares [EMAIL PROTECTED]; - */ -OUTPUT_FORMAT(elf32-i386, elf32-i386, elf32-i386) +/* Default linker script, for normal executables */ +OUTPUT_FORMAT(elf32-i386, elf32-i386, + elf32-i386) That's just a whitespace change and removal of credit. +SEARCH_DIR(/usr/i586-suse-linux/lib); SEARCH_DIR(/usr/local/lib); I haven't got SuSE. The next hunk is another huge multi-page whitespace change with code changes sprinkled in it. I have no idea what this patch does, but the second hunk is suse-specific and the second half of it is for qemu-ppc which builds runs for me. (Dunno if it _works_, but it's not segfaulting immediately when I run it...) Rob -- One of my most productive days was throwing away 1000 lines of code. - Ken Thompson.
Re: [Qemu-devel] [PATCH] qemu-i386 segfaults running hello world.
Am 10.07.2007 um 17:47 schrieb Rob Landley: I have no idea what this patch does, but the second hunk is suse- specific and the second half of it is for qemu-ppc which builds runs for me. (Dunno if it _works_, but it's not segfaulting immediately when I run it...) ppc-softmmu does not build on OS X for me, there are two undefined symbol references, caused in some way by function aliasing. Would be nice if someone could fix that in CVS. I got a number of error messages and an (emulated) crash when booting a Debian CD on both ppc and ppc64 so am unsure whether it's my quickfix (attached) or normal behavior. :-) Andreas ppc-2007-07-10.diff Description: Binary data
Re: [Qemu-devel] [PATCH] qemu-i386 segfaults running hello world.
Hi,
this is the patch we are currently using to build qemu-0.9.0. Does this
work for you?
Alex
--- i386.ld
+++ i386.ld
@@ -1,116 +1,164 @@
-/* ld script to make i386 Linux kernel
- * Written by Martin Mares [EMAIL PROTECTED];
- */
-OUTPUT_FORMAT(elf32-i386, elf32-i386, elf32-i386)
+/* Default linker script, for normal executables */
+OUTPUT_FORMAT(elf32-i386, elf32-i386,
+ elf32-i386)
OUTPUT_ARCH(i386)
-SEARCH_DIR(/lib); SEARCH_DIR(/usr/lib); SEARCH_DIR(/usr/local/lib); SEARCH_DIR(/usr/alpha-unknown-linux-gnu/lib);
ENTRY(_start)
+SEARCH_DIR(/usr/i586-suse-linux/lib); SEARCH_DIR(/usr/local/lib); SEARCH_DIR(/lib); SEARCH_DIR(/usr/lib);
SECTIONS
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Re: [Qemu-devel] [PATCH] qemu-i386 segfaults running hello world.
Rob Landley schrieb:
Ok, it's a more fundamental problem:
[EMAIL PROTECTED]:/sys$ qemu-i386
Segmentation fault (core dumped)
Nothing to do with the program it's trying to run, it segfaults with no
arguments.
Is anybody else seeing this?
Rob
Yes, I see this on Debian Linux since several months (libc update?).
The crash is caused by libc startup code which calls a null pointer.
QEMU provides this null pointer with the __init_array_start
workaround in linux-user/main.c.
This can be fixed with some kind of code hack - see my patch
(which is not really a solution, but one more workaround).
Nevertheless user mode emulations remains unusable even
with this patch because of TLS problems.
Regards,
Stefan
Index: linux-user/main.c
===
RCS file: /sources/qemu/qemu/linux-user/main.c,v
retrieving revision 1.116
diff -u -b -B -r1.116 main.c
--- linux-user/main.c 21 Jun 2007 22:55:02 - 1.116
+++ linux-user/main.c 23 Jun 2007 11:03:42 -
@@ -45,12 +45,16 @@
/* for recent libc, we add these dummy symbols which are not declared
when generating a linked object (bug in ld ?) */
#if (__GLIBC__ 2 || (__GLIBC__ == 2 __GLIBC_MINOR__ = 3)) !defined(CONFIG_STATIC)
-long __preinit_array_start[0];
-long __preinit_array_end[0];
-long __init_array_start[0];
-long __init_array_end[0];
-long __fini_array_start[0];
-long __fini_array_end[0];
+typedef void (*dummy_function_t)(void);
+static void dummy_function(void)
+{
+}
+dummy_function_t __preinit_array_start = dummy_function;
+dummy_function_t __preinit_array_end = dummy_function;
+dummy_function_t __init_array_start = dummy_function;
+dummy_function_t __init_array_end = dummy_function;
+dummy_function_t __fini_array_start = dummy_function;
+dummy_function_t __fini_array_end = dummy_function;
#endif
/* XXX: on x86 MAP_GROWSDOWN only works if ESP = address + 32, so
