Re: [PATCH] Prevent trace call into unloaded module text
Wu Fengguang wrote: Below is the updated patch. Applied, thanks. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] Prevent trace call into unloaded module text
On Wed, Nov 26, 2008 at 01:17:55PM +0200, Avi Kivity wrote: Wu Fengguang wrote: Add marker_synchronize_unregister() before module unloading. This prevents possible trace calls into unloaded module text. Signed-off-by: Wu Fengguang [EMAIL PROTECTED] --- diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a87f45e..64f38b3 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2102,5 +2102,6 @@ void kvm_exit(void) kvm_arch_exit(); kvm_exit_debug(); __free_page(bad_page); + marker_synchronize_unregister(); } EXPORT_SYMBOL_GPL(kvm_exit); What about kvm-intel.ko and kvm-amd.ko? They also contain markers. vmx_exit and svm_exit() all calls into kvm_exit(), so they have been handled in a common way. (and, why doesn't module unload do this automatically?) Maybe most modules don't need it for now? Thanks, Fengguang -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] Prevent trace call into unloaded module text
On Wed, Nov 26, 2008 at 07:46:19PM +0800, Wu Fengguang wrote: On Wed, Nov 26, 2008 at 01:17:55PM +0200, Avi Kivity wrote: Wu Fengguang wrote: Add marker_synchronize_unregister() before module unloading. This prevents possible trace calls into unloaded module text. Signed-off-by: Wu Fengguang [EMAIL PROTECTED] --- diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a87f45e..64f38b3 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2102,5 +2102,6 @@ void kvm_exit(void) kvm_arch_exit(); kvm_exit_debug(); __free_page(bad_page); + marker_synchronize_unregister(); } EXPORT_SYMBOL_GPL(kvm_exit); What about kvm-intel.ko and kvm-amd.ko? They also contain markers. vmx_exit and svm_exit() all calls into kvm_exit(), so they have been handled in a common way. (and, why doesn't module unload do this automatically?) Maybe most modules don't need it for now? OK I got a better answer: because marker_synchronize_unregister() must be called after marker_probe_unregister() calls and the tear down of any private data the trace functions rely on. So there are no automatic way. Below is the updated patch. Thanks, Fengguang --- Prevent trace call into torn down text or data Add marker_synchronize_unregister() immediately after probe unregisters. This prevents possible trace calls into unloaded module text, or the trace functions accessing invalidated data. Signed-off-by: Wu Fengguang [EMAIL PROTECTED] --- diff --git a/virt/kvm/kvm_trace.c b/virt/kvm/kvm_trace.c index 41dcc84..f598744 100644 --- a/virt/kvm/kvm_trace.c +++ b/virt/kvm/kvm_trace.c @@ -252,6 +252,7 @@ void kvm_trace_cleanup(void) struct kvm_trace_probe *p = kvm_trace_probes[i]; marker_probe_unregister(p-name, p-probe_func, p); } + marker_synchronize_unregister(); relay_close(kt-rchan); debugfs_remove(kt-lost_file); -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] Prevent trace call into unloaded module text
Wu Fengguang wrote: Add marker_synchronize_unregister() before module unloading. This prevents possible trace calls into unloaded module text. Signed-off-by: Wu Fengguang [EMAIL PROTECTED] --- diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a87f45e..64f38b3 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2102,5 +2102,6 @@ void kvm_exit(void) kvm_arch_exit(); kvm_exit_debug(); __free_page(bad_page); + marker_synchronize_unregister(); } EXPORT_SYMBOL_GPL(kvm_exit); What about kvm-intel.ko and kvm-amd.ko? They also contain markers. (and, why doesn't module unload do this automatically?) -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH] Prevent trace call into unloaded module text
Add marker_synchronize_unregister() before module unloading. This prevents possible trace calls into unloaded module text. Signed-off-by: Wu Fengguang [EMAIL PROTECTED] --- diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a87f45e..64f38b3 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2102,5 +2102,6 @@ void kvm_exit(void) kvm_arch_exit(); kvm_exit_debug(); __free_page(bad_page); + marker_synchronize_unregister(); } EXPORT_SYMBOL_GPL(kvm_exit); -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
