From bc9540e842eb5639ca59cb133adef211d252843c Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Mon, 23 Feb 2015 13:03:10 +0000 Subject: [PATCH] gdbserver: 64-bit kernel / 32-inferior, syscall restarting $ make check RUNTESTFLAGS="--target_board=native-gdbserver/-m32 clone-thread_db.exp" gdb.log shows: Running target native-gdbserver/-m32 ... clone-thread_db: src/gdb/testsuite/gdb.threads/clone-thread_db.c:57: thread_fn: Assertion `res != -1' failed. ... (gdb) FAIL: gdb.threads/clone-thread_db.exp: continue to end That was waitpid returning -1 / EINTR. We don't see that when testing with unix/-m32 (native debugging). Turns out to be that when debugging a 32-bit inferior, a 64-bit GDBserver is reading/writing $orig_eax from/to the wrong ptrace register buffer offset. When gdbserver is 64-bit, the ptrace register buffer is in 64-bit layout, so the register is found at "ORIG_EAX * 8", not at "ORIG_EAX * 4". Fixes these with --target_board=native-gdbserver/-m32 on x86_64 Fedora 20: -FAIL: gdb.threads/clone-thread_db.exp: continue to end +PASS: gdb.threads/clone-thread_db.exp: continue to end -FAIL: gdb.threads/hand-call-in-threads.exp: all dummies popped +PASS: gdb.threads/hand-call-in-threads.exp: all dummies popped PASS: gdb.threads/hand-call-in-threads.exp: breakpoint on all_threads_running PASS: gdb.threads/hand-call-in-threads.exp: breakpoint on hand_call PASS: gdb.threads/hand-call-in-threads.exp: disable scheduler locking @@ -29339,15 +29331,15 @@ PASS: gdb.threads/hand-call-in-threads.e PASS: gdb.threads/hand-call-in-threads.exp: discard hand call, thread 4 PASS: gdb.threads/hand-call-in-threads.exp: discard hand call, thread 5 PASS: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 1 -FAIL: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 2 -FAIL: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 3 -FAIL: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 4 +PASS: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 2 +PASS: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 3 +PASS: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 4 PASS: gdb.threads/hand-call-in-threads.exp: dummy stack frame number, thread 5 PASS: gdb.threads/hand-call-in-threads.exp: enable scheduler locking PASS: gdb.threads/hand-call-in-threads.exp: hand call, thread 1 -FAIL: gdb.threads/hand-call-in-threads.exp: hand call, thread 2 -FAIL: gdb.threads/hand-call-in-threads.exp: hand call, thread 3 -FAIL: gdb.threads/hand-call-in-threads.exp: hand call, thread 4 +PASS: gdb.threads/hand-call-in-threads.exp: hand call, thread 2 +PASS: gdb.threads/hand-call-in-threads.exp: hand call, thread 3 +PASS: gdb.threads/hand-call-in-threads.exp: hand call, thread 4 PASS: gdb.threads/hand-call-in-threads.exp: hand call, thread 5 PASS: gdb.threads/hand-call-in-threads.exp: prepare to discard hand call, thread 1 PASS: gdb.threads/hand-call-in-threads.exp: prepare to discard hand call, thread 2 gdb/gdbserver/ChangeLog 2015-02-23 Pedro Alves * linux-x86-low.c (REGSIZE): Define in both 32-bit and 64-bit modes. (x86_fill_gregset, x86_store_gregset): Use it when handling $orig_eax. --- gdb/gdbserver/ChangeLog | 7 +++++++ gdb/gdbserver/linux-x86-low.c | 7 +++++-- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index cfdb3e7..d724e6c 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,10 @@ +2015-02-23 Pedro Alves + + * linux-x86-low.c (REGSIZE): Define in both 32-bit and 64-bit + modes. + (x86_fill_gregset, x86_store_gregset): Use it when handling + $orig_eax. + 2015-02-20 Pedro Alves * thread-db.c: Include "nat/linux-procfs.h". diff --git a/gdb/gdbserver/linux-x86-low.c b/gdb/gdbserver/linux-x86-low.c index 2c3fccc..e58a7ac 100644 --- a/gdb/gdbserver/linux-x86-low.c +++ b/gdb/gdbserver/linux-x86-low.c @@ -176,6 +176,7 @@ static /*const*/ int i386_regmap[] = /* So code below doesn't have to care, i386 or amd64. */ #define ORIG_EAX ORIG_RAX +#define REGSIZE 8 static const int x86_64_regmap[] = { @@ -221,6 +222,8 @@ static /*const*/ int i386_regmap[] = #define I386_NUM_REGS (sizeof (i386_regmap) / sizeof (i386_regmap[0])) +#define REGSIZE 4 + #endif #ifdef __x86_64__ @@ -374,7 +377,7 @@ x86_fill_gregset (struct regcache *regcache, void *buf) collect_register (regcache, i, ((char *) buf) + i386_regmap[i]); collect_register_by_name (regcache, "orig_eax", - ((char *) buf) + ORIG_EAX * 4); + ((char *) buf) + ORIG_EAX * REGSIZE); } static void @@ -396,7 +399,7 @@ x86_store_gregset (struct regcache *regcache, const void *buf) supply_register (regcache, i, ((char *) buf) + i386_regmap[i]); supply_register_by_name (regcache, "orig_eax", - ((char *) buf) + ORIG_EAX * 4); + ((char *) buf) + ORIG_EAX * REGSIZE); } static void -- 2.7.4