dtrace: ensure that arg6 through arg9 get retrieved correctly for USDT probes

A bug in the implementation of retrieving arguments from the stack caused
bogus values to be returned for arg6 through arg9 on x86_64.  This has been
resolved.

This commit also removes various debugging output that is no longer needed.

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>

diff --git a/kernel/dtrace/dtrace_os.c b/kernel/dtrace/dtrace_os.c
index 2eadab19017b47e4d1cfe6ea15e7904109dab533..0ceadf6f15e4e7c0dd7ec3ed073ed6d9420bce6a 100644 (file)
--- a/kernel/dtrace/dtrace_os.c
+++ b/kernel/dtrace/dtrace_os.c
@@ -982,7 +982,6 @@ static int handler(struct uprobe_consumer *self, struct pt_regs *regs)
                                                    fmtp_cns);
        int                     rc = 0;
 
-       pr_info("USDT-HANDLER: Called for PC %lx\n", GET_IP(regs));
        read_lock(&this_cpu_core->cpu_ft_lock);
        if (dtrace_tracepoint_hit == NULL)
                pr_warn("Fasttrap probes, but no handler\n");
@@ -1019,10 +1018,8 @@ int dtrace_tracepoint_enable(pid_t pid, uintptr_t addr,
 
        ino = vma->vm_file->f_mapping->host;
        off = ((loff_t)vma->vm_pgoff << PAGE_SHIFT) + (addr - vma->vm_start);
-pr_info("DEBUG: PID %d: vma 0x%p, mapping 0x%p, inode 0x%p, offset 0x%llx\n", pid, vma, vma->vm_file->f_mapping, ino, off);
 
        if (((uintptr_t)ino & 0xffff880000000000ULL) == 0xffff880000000000ULL) {
-pr_info("DEBUG: Registering uprobe...\n");
                mtp->fmtp_cns.handler = handler;
 
                rc = uprobe_register(ino, off, &mtp->fmtp_cns);
@@ -1057,7 +1054,6 @@ int dtrace_tracepoint_disable(pid_t pid, fasttrap_machtp_t *mtp)
                return -ENOENT;
        }
 
-pr_info("DEBUG: Unregistering uprobe...\n");
        uprobe_unregister(mtp->fmtp_ino, mtp->fmtp_off, &mtp->fmtp_cns);
 
        mtp->fmtp_ino = NULL;