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From: Laurent Vivier <laurent@vivier.eu>
To: qemu-devel@nongnu.org
Cc: Laurent Vivier <laurent@vivier.eu>,
	Filip Bozuta <Filip.Bozuta@syrmia.com>
Subject: [PATCH] linux-user: fix the errno value in print_syscall_err()
Date: Tue,  7 Jul 2020 19:11:15 +0200	[thread overview]
Message-ID: <20200707171115.533166-1-laurent@vivier.eu> (raw)

errno of the target is returned as a negative value by the syscall,
not in the host errno variable.

The emulation of the target syscall can return an error while the
host doesn't set an errno value. Target errnos and host errnos can
also differ in some cases.

Fixes: c84be71f6854 ("linux-user: Extend strace support to enable argument printing after syscall execution")
Cc: Filip.Bozuta@syrmia.com
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/strace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/linux-user/strace.c b/linux-user/strace.c
index 5235b2260cdd..b42664bbd180 100644
--- a/linux-user/strace.c
+++ b/linux-user/strace.c
@@ -731,7 +731,7 @@ print_syscall_err(abi_long ret)
 
     qemu_log(" = ");
     if (ret < 0) {
-        qemu_log("-1 errno=%d", errno);
+        qemu_log("-1 errno=%d", (int)-ret);
         errstr = target_strerror(-ret);
         if (errstr) {
             qemu_log(" (%s)", errstr);
-- 
2.26.2



                 reply	other threads:[~2020-07-07 17:12 UTC|newest]

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