Commit f6a6bc7350 for qemu.org
commit f6a6bc735015e7db9e20650f05496fed9a7e77ec
Author: Liam Merwick <liam.merwick@oracle.com>
Date: Fri May 23 16:01:34 2025 +0000
hw/xen: Fix trace_xs_node_read() params
When the '--enable-trace-backends=syslog' build option is configured,
the following compilation error is encountered.
In file included from /usr/include/sys/syslog.h:207,
from /usr/include/syslog.h:1,
from ./trace/trace-hw_xen.h:224,
from ../hw/xen/trace.h:1,
from ../hw/xen/xen-bus-helper.c:13:
In function ‘syslog’,
inlined from ‘_nocheck__trace_xs_node_read’ at ../hw/xen/trace-events:41:9,
inlined from ‘trace_xs_node_read’ at trace/trace-hw_xen.h:903:9,
inlined from ‘xs_node_read’ at ../hw/xen/xen-bus-helper.c:154:5:
/usr/include/bits/syslog.h:45:3: error: ‘%s’ directive argument is null [-Werror=format-overflow=]
45 | __syslog_chk (__pri, __USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Add a check that 'value' is not null before passing it to trace_xs_node_read().
Fixes: e6cdeee95990 ("hw/xen: Add xs_node_read() helper function")
Signed-off-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Message-ID: <20250523160134.218997-1-liam.merwick@oracle.com>
Signed-off-by: Anthony PERARD <anthony.perard@vates.tech>
diff --git a/hw/xen/xen-bus-helper.c b/hw/xen/xen-bus-helper.c
index 288fad422b..1087a585cc 100644
--- a/hw/xen/xen-bus-helper.c
+++ b/hw/xen/xen-bus-helper.c
@@ -151,7 +151,7 @@ char *xs_node_read(struct qemu_xs_handle *h, xs_transaction_t tid,
va_end(ap);
value = qemu_xen_xs_read(h, tid, path, len);
- trace_xs_node_read(path, value);
+ trace_xs_node_read(path, value ? value : "<null>");
if (!value) {
error_setg_errno(errp, errno, "failed to read from '%s'", path);
}