From: Keir Fraser Date: Thu, 12 Mar 2009 11:09:57 +0000 (+0000) Subject: Domain core-dumping fixes X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~13992^2~95 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=fb0a30b839c4dbe13fafe63c47446485e86668f7;p=xen.git Domain core-dumping fixes The code was attempting to use the domain's current number of pages (info.nr_pages) as a maximum index. We then walk the memory map and can easily over-write past the end of the nr_pages-sized array, if the domain has more pages mapped in than earlier (live dump). Restrict ourselves to the current number of pages. Also fix the dump core method in xend to actually implement the crash and live options. In particular this means that xend clients other than xm now get non-live dumps by default. Signed-off-by: John Levon --- diff --git a/tools/libxc/xc_core.c b/tools/libxc/xc_core.c index a7fd1647f3..ef1e8dd7a1 100644 --- a/tools/libxc/xc_core.c +++ b/tools/libxc/xc_core.c @@ -518,7 +518,17 @@ xc_domain_dumpcore_via_callback(int xc_handle, if ( sts != 0 ) goto out; + /* + * Note: this is the *current* number of pages and may change under + * a live dump-core. We'll just take this value, and if more pages + * exist, we'll skip them. If there's less, then we'll just not use + * all the array... + * + * We don't want to use the total potential size of the memory map + * since that is usually much higher than info.nr_pages. + */ nr_pages = info.nr_pages; + if ( !auto_translated_physmap ) { /* obtain p2m table */ diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h index 93fbd8be67..75995b1a92 100644 --- a/tools/libxc/xenctrl.h +++ b/tools/libxc/xenctrl.h @@ -158,7 +158,7 @@ typedef struct xc_dominfo { paused:1, blocked:1, running:1, hvm:1, debugged:1; unsigned int shutdown_reason; /* only meaningful if shutdown==1 */ - unsigned long nr_pages; + unsigned long nr_pages; /* current number, not maximum */ unsigned long shared_info_frame; uint64_t cpu_time; unsigned long max_memkb; diff --git a/tools/python/xen/xend/XendDomain.py b/tools/python/xen/xend/XendDomain.py index d1bfaa3f43..bba98f596b 100644 --- a/tools/python/xen/xend/XendDomain.py +++ b/tools/python/xen/xend/XendDomain.py @@ -1237,13 +1237,23 @@ class XendDomain: POWER_STATE_NAMES[DOM_STATE_PAUSED], POWER_STATE_NAMES[dominfo._stateGet()]) + dopause = (not live and dominfo._stateGet() == DOM_STATE_RUNNING) + if dopause: + dominfo.pause() + try: - log.info("Domain core dump requested for domain %s (%d) " - "live=%d crash=%d.", - dominfo.getName(), dominfo.getDomid(), live, crash) - return dominfo.dumpCore(filename) - except Exception, ex: - raise XendError(str(ex)) + try: + log.info("Domain core dump requested for domain %s (%d) " + "live=%d crash=%d.", + dominfo.getName(), dominfo.getDomid(), live, crash) + dominfo.dumpCore(filename) + if crash: + self.domain_destroy(domid) + except Exception, ex: + raise XendError(str(ex)) + finally: + if dopause and not crash: + dominfo.unpause() def domain_destroy(self, domid): """Terminate domain immediately. diff --git a/tools/python/xen/xend/XendDomainInfo.py b/tools/python/xen/xend/XendDomainInfo.py index 4ec5679fb8..7b40d46de5 100644 --- a/tools/python/xen/xend/XendDomainInfo.py +++ b/tools/python/xen/xend/XendDomainInfo.py @@ -2027,26 +2027,31 @@ class XendDomainInfo: @raise: XendError if core dumping failed. """ - try: - if not corefile: - this_time = time.strftime("%Y-%m%d-%H%M.%S", time.localtime()) - corefile = "/var/xen/dump/%s-%s.%s.core" % (this_time, - self.info['name_label'], self.domid) + if not corefile: + this_time = time.strftime("%Y-%m%d-%H%M.%S", time.localtime()) + corefile = "/var/xen/dump/%s-%s.%s.core" % (this_time, + self.info['name_label'], self.domid) - if os.path.isdir(corefile): - raise XendError("Cannot dump core in a directory: %s" % - corefile) - - self._writeVm(DUMPCORE_IN_PROGRESS, 'True') - xc.domain_dumpcore(self.domid, corefile) - self._removeVm(DUMPCORE_IN_PROGRESS) - except RuntimeError, ex: - corefile_incomp = corefile+'-incomplete' - os.rename(corefile, corefile_incomp) + if os.path.isdir(corefile): + raise XendError("Cannot dump core in a directory: %s" % + corefile) + + try: + try: + self._writeVm(DUMPCORE_IN_PROGRESS, 'True') + xc.domain_dumpcore(self.domid, corefile) + except RuntimeError, ex: + corefile_incomp = corefile+'-incomplete' + try: + os.rename(corefile, corefile_incomp) + except: + pass + + log.error("core dump failed: id = %s name = %s: %s", + self.domid, self.info['name_label'], str(ex)) + raise XendError("Failed to dump core: %s" % str(ex)) + finally: self._removeVm(DUMPCORE_IN_PROGRESS) - log.exception("XendDomainInfo.dumpCore failed: id = %s name = %s", - self.domid, self.info['name_label']) - raise XendError("Failed to dump core: %s" % str(ex)) # # Device creation/deletion functions diff --git a/tools/python/xen/xm/main.py b/tools/python/xen/xm/main.py index 2ffa50a0fe..c8bf32174c 100644 --- a/tools/python/xen/xm/main.py +++ b/tools/python/xen/xm/main.py @@ -1351,22 +1351,10 @@ def xm_dump_core(args): else: filename = None - if not live: - ds = server.xend.domain.pause(dom, True) - - try: - print "Dumping core of domain: %s ..." % str(dom) - server.xend.domain.dump(dom, filename, live, crash) - - if crash: - print "Destroying domain: %s ..." % str(dom) - server.xend.domain.destroy(dom) - elif reset: - print "Resetting domain: %s ..." % str(dom) - server.xend.domain.reset(dom) - finally: - if not live and not crash and not reset and ds == DOM_STATE_RUNNING: - server.xend.domain.unpause(dom) + print "Dumping core of domain: %s ..." % str(dom) + server.xend.domain.dump(dom, filename, live, crash) + if reset: + server.xend.domain.reset(dom) def xm_rename(args): arg_check(args, "rename", 2)