tracing: Propagate is_signed to expression

commit 097f1eefedeab528cecbd35586dfe293853ffb17 upstream.

During expression parsing, a new expression field is created which
should inherit the properties of the operands, such as size and
is_signed.

is_signed propagation was missing, causing spurious errors with signed
operands.  Add it in parse_expr() and parse_unary() to fix the problem.

Link: https://lkml.kernel.org/r/f4dac08742fd7a0920bf80a73c6c44042f5eaa40.1643319703.git.zanussi@kernel.org
Cc: stable@vger.kernel.org
Fixes: 100719dcef447 ("tracing: Add simple expression support to hist triggers")
Reported-by: Yordan Karadzhov <ykaradzhov@vmware.com>
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215513
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 83efce3a87ca74814aa77081a4258314d695cbeb..918f969dffcfe22288b9c43ba478310fb6185759 100644 (file)
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -2220,6 +2220,8 @@ static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
                (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
        expr->fn = hist_field_unary_minus;
        expr->operands[0] = operand1;
+       expr->size = operand1->size;
+       expr->is_signed = operand1->is_signed;
        expr->operator = FIELD_OP_UNARY_MINUS;
        expr->name = expr_str(expr, 0);
        expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
@@ -2359,6 +2361,7 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
 
        /* The operand sizes should be the same, so just pick one */
        expr->size = operand1->size;
+       expr->is_signed = operand1->is_signed;
 
        expr->operator = field_op;
        expr->name = expr_str(expr, 0);