From 931df711f2b833898038e61f1fa807761aa904d7 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Wed, 10 Feb 2010 13:30:16 +0000 Subject: [PATCH] libxc: fix bug in xc_tbuf_get_size() The size in pages of trace buffer should be t_info->tbuf_size rather than t_info pages. Signed-off-by: Yu Zhiguo --- tools/libxc/xc_tbuf.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/tools/libxc/xc_tbuf.c b/tools/libxc/xc_tbuf.c index 3948d0af7d..aa21d849bb 100644 --- a/tools/libxc/xc_tbuf.c +++ b/tools/libxc/xc_tbuf.c @@ -15,6 +15,7 @@ */ #include "xc_private.h" +#include static int tbuf_enable(int xc_handle, int enable) { @@ -44,6 +45,7 @@ int xc_tbuf_set_size(int xc_handle, unsigned long size) int xc_tbuf_get_size(int xc_handle, unsigned long *size) { + struct t_info *t_info; int rc; DECLARE_SYSCTL; @@ -52,9 +54,19 @@ int xc_tbuf_get_size(int xc_handle, unsigned long *size) sysctl.u.tbuf_op.cmd = XEN_SYSCTL_TBUFOP_get_info; rc = xc_sysctl(xc_handle, &sysctl); - if (rc == 0) - *size = sysctl.u.tbuf_op.size; - return rc; + if ( rc != 0 ) + return rc; + + t_info = xc_map_foreign_range(xc_handle, DOMID_XEN, + sysctl.u.tbuf_op.size, PROT_READ | PROT_WRITE, + sysctl.u.tbuf_op.buffer_mfn); + + if ( t_info == NULL || t_info->tbuf_size == 0 ) + return -1; + + *size = t_info->tbuf_size; + + return 0; } int xc_tbuf_enable(int xc_handle, unsigned long pages, unsigned long *mfn, -- 2.30.2