kdb: Get rid of confusing diag msg from "rd" if current task has no regs
If you switch to a sleeping task with the "pid" command and then type
"rd", kdb tells you this:
No current kdb registers. You may need to select another task
diag: -17: Invalid register name
The first message makes sense, but not the second. Fix it by just
returning 0 after commands accessing the current registers finish if
we've already printed the "No current kdb registers" error.
While fixing kdb_rd(), change the function to use "if" rather than
"ifdef". It cleans the function up a bit and any modern compiler will
have no trouble handling still producing good code.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191109111624.5.I121f4c6f0c19266200bf6ef003de78841e5bfc3d@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index ba12e9f..b22292b 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -543,9 +543,8 @@ int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
if (diag)
return diag;
} else if (symname[0] == '%') {
- diag = kdb_check_regs();
- if (diag)
- return diag;
+ if (kdb_check_regs())
+ return 0;
/* Implement register values with % at a later time as it is
* arch optional.
*/
@@ -1836,8 +1835,7 @@ static int kdb_go(int argc, const char **argv)
*/
static int kdb_rd(int argc, const char **argv)
{
- int len = kdb_check_regs();
-#if DBG_MAX_REG_NUM > 0
+ int len = 0;
int i;
char *rname;
int rsize;
@@ -1846,8 +1844,14 @@ static int kdb_rd(int argc, const char **argv)
u16 reg16;
u8 reg8;
- if (len)
- return len;
+ if (kdb_check_regs())
+ return 0;
+
+ /* Fallback to Linux showregs() if we don't have DBG_MAX_REG_NUM */
+ if (DBG_MAX_REG_NUM <= 0) {
+ kdb_dumpregs(kdb_current_regs);
+ return 0;
+ }
for (i = 0; i < DBG_MAX_REG_NUM; i++) {
rsize = dbg_reg_def[i].size * 2;
@@ -1889,12 +1893,7 @@ static int kdb_rd(int argc, const char **argv)
}
}
kdb_printf("\n");
-#else
- if (len)
- return len;
- kdb_dumpregs(kdb_current_regs);
-#endif
return 0;
}
@@ -1928,9 +1927,8 @@ static int kdb_rm(int argc, const char **argv)
if (diag)
return diag;
- diag = kdb_check_regs();
- if (diag)
- return diag;
+ if (kdb_check_regs())
+ return 0;
diag = KDB_BADREG;
for (i = 0; i < DBG_MAX_REG_NUM; i++) {