Hi Denys,
> Applied both patches, thanks.
Thanks! FYI I just realised my git tree was pointing at an old URL:
git://strace.git.sourceforge.net/gitroot/strace/strace
Would it be worth shutting that tree down if it is no longer in use?
> Can you take a look at the silly dance we do with ppc_result variable?
>
> get_syscall_result():
>
> ppc_result = ppc_regs.gpr[3];
> if (ppc_regs.ccr & SO_MASK)
> ppc_result = -ppc_result;
>
>
> later, get_error():
>
> if (check_errno && is_negated_errno(ppc_result)) {
> tcp->u_rval = -1;
> u_error = -ppc_result;
> }
> else {
> tcp->u_rval = ppc_result;
> }
>
> From this, looks like PPC does NOT use "if it's negative
> and below max errno" logic - it has a dedicated error bit,
> SO_MASK. But our code shoehorn it into that logic.
>
> Shouldn't get_syscall_result() code bit just nixed,
> and get_error() changed to this? -
>
> if (ppc_regs.ccr & SO_MASK) {
> tcp->u_rval = -1;
> u_error = ppc_regs.gpr[3];
> }
> else {
> tcp->u_rval = ppc_regs.gpr[3];
> }
This looks good and is much simpler. I ran a few tests to verify we
get reasonable output for failing system calls.
> get_regs():
>
> get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (long)
> &ppc_regs); if (get_regs_error && errno == EIO)
> get_regs_error = powerpc_getregs_old(pid);
>
> The fallback will be taken _every time_ on old kernels.
> Meaning, we will try PTRACE_GETREGS pointlessly twice per syscall.
> We should remember the first failure instead.
>
> Care to fix and test these problems?
Thanks for doing this too. A simple build fix below.
Anton
--
powerpc: Fix iflag build issue
Commit 6b3016e43 (POWERPC: read ppc_regs.nip if -i) cause a build
breakage. Fix it by making iflag global.
Signed-off-by: Anton Blanchard <an...@samba.org>
---
diff --git a/defs.h b/defs.h
index 64cfc8d..6e0bd88 100644
--- a/defs.h
+++ b/defs.h
@@ -550,6 +550,7 @@ typedef enum {
extern cflag_t cflag;
extern bool debug_flag;
extern bool Tflag;
+extern bool iflag;
extern unsigned int qflag;
extern bool not_failing_only;
extern bool show_fd_path;
diff --git a/strace.c b/strace.c
index 94706ad..9aa2b36 100644
--- a/strace.c
+++ b/strace.c
@@ -78,10 +78,10 @@ bool need_fork_exec_workarounds = 0;
bool debug_flag = 0;
bool Tflag = 0;
unsigned int qflag = 0;
+bool iflag = 0;
/* Which WSTOPSIG(status) value marks syscall traps? */
static unsigned int syscall_trap_sig = SIGTRAP;
static unsigned int tflag = 0;
-static bool iflag = 0;
static bool rflag = 0;
static bool print_pid_pfx = 0;
------------------------------------------------------------------------------
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