git: 256c8c5df2a4 - main - dt_unring_buf: set dtbd_oldest to the start of the first record

The branch main has been updated by avg:

URL: https://cgit.FreeBSD.org/src/commit/?id=256c8c5df2a4bdd43afd9ec5a2f8be9374284e1e

commit 256c8c5df2a4bdd43afd9ec5a2f8be9374284e1e
Author:     Andriy Gapon <avg@FreeBSD.org>
AuthorDate: 2022-01-11 13:44:04 +0000
Commit:     Andriy Gapon <avg@FreeBSD.org>
CommitDate: 2022-01-11 13:44:04 +0000

    dt_unring_buf: set dtbd_oldest to the start of the first record
    
    It was set to the start of the buffer and that can be different from the
    start of teh first record because of a misalignment.
    
    This change follows the example of dt_realloc_buf().
    
    Reviewed by:    tsoome, markj
    MFC after:      4 weeks
    Differential Revision:  https://reviews.freebsd.org/D33649
---
 cddl/contrib/opensolaris/lib/libdtrace/common/dt_consume.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_consume.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_consume.c
index 811c88bbf0ad..862d4b9222d7 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_consume.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_consume.c
@@ -2621,7 +2621,7 @@ dt_unring_buf(dtrace_hdl_t *dtp, dtrace_bufdesc_t *buf)
 	bcopy(buf->dtbd_data, ndp, buf->dtbd_oldest);
 
 	dt_free(dtp, buf->dtbd_data);
-	buf->dtbd_oldest = 0;
+	buf->dtbd_oldest = misalign;
 	buf->dtbd_data = newdata;
 	buf->dtbd_size += misalign;