From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: [PATCH] tools/libxc: fix error handling in xc_mem_paging_load Date: Wed, 18 Jan 2012 18:15:24 +0100 Message-ID: <1821b0e1ce16d0015542.1326906924@probook.site> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org # HG changeset patch # User Olaf Hering # Date 1326906775 -3600 # Node ID 1821b0e1ce16d0015542d4164505d97f130f09d7 # Parent 15ab61865ecbd146f6ce65fbea5bf49bfd9c6cb1 tools/libxc: fix error handling in xc_mem_paging_load xc_mem_paging_load() does not pass errors in errno and the actual errno from xc_mem_event_control() is overwritten by munlock(). xenpaging_populate_page() needs to check errno, but with the switch to xc_mem_paging_load() it could not receive ENOMEM anymore. Update xc_mem_paging_load() to return -1 and preserve errno during munlock(). Signed-off-by: Olaf Hering diff -r 15ab61865ecb -r 1821b0e1ce16 tools/libxc/xc_mem_paging.c --- a/tools/libxc/xc_mem_paging.c +++ b/tools/libxc/xc_mem_paging.c @@ -68,23 +68,28 @@ int xc_mem_paging_prep(xc_interface *xch int xc_mem_paging_load(xc_interface *xch, domid_t domain_id, unsigned long gfn, void *buffer) { - int rc; + int rc, old_errno; + + errno = -EINVAL; if ( !buffer ) - return -EINVAL; + return -1; if ( ((unsigned long) buffer) & (XC_PAGE_SIZE - 1) ) - return -EINVAL; + return -1; if ( mlock(buffer, XC_PAGE_SIZE) ) - return -errno; + return -1; rc = xc_mem_event_control(xch, domain_id, XEN_DOMCTL_MEM_EVENT_OP_PAGING_PREP, XEN_DOMCTL_MEM_EVENT_OP_PAGING, buffer, NULL, gfn); - (void)munlock(buffer, XC_PAGE_SIZE); + old_errno = errno; + munlock(buffer, XC_PAGE_SIZE); + errno = old_errno; + return rc; }