From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755239AbaHKWcM (ORCPT ); Mon, 11 Aug 2014 18:32:12 -0400 Received: from mail-qc0-f180.google.com ([209.85.216.180]:65065 "EHLO mail-qc0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751743AbaHKWcK (ORCPT ); Mon, 11 Aug 2014 18:32:10 -0400 From: Sadasivan Shaiju MIME-Version: 1.0 X-Mailer: Microsoft Outlook 14.0 Thread-Index: Ac+1s52Yj9OQSKiBRgGebj+R0X9P6w== Date: Mon, 11 Aug 2014 15:31:58 -0700 Message-ID: Subject: [PATCH] kgdb: Ignore DIE_PAGE_FAULT event in notify handler [2.6.32] kernel To: jason.wessel@windriver.com Cc: linux-kernel@vger.kernel.org, shaiju_sada@yahoo.com Content-Type: multipart/mixed; boundary=001a11c1ec1629fc4c0500622092 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --001a11c1ec1629fc4c0500622092 Content-Type: text/plain; charset=UTF-8 Hi , I work for Montavista (Cavium Inc) as a Technical Lead . I want to push some of the kernel patches to rt community (2.6.32 kernel 2.6.33 rt patch) , so that It will go to the main line These patches are reviewed and approved by our system Architect. I request you to include in the main line . These issues were reported by our customer CISCO . Problem Description: If kprobes is enabled along with kgdb, kgdb gives a SIGHUP on the host side. Root Cause: Inside the do_page_fault() (arch/mips/mm/fault.c) there is a call to notify_die() when kprobes is enabled. When kgdb is enabled the register_die_notifier() handler catches this exception (which is 3 - TLB miss on store) and says it does not know it and returns it as a SIGHUP. How Solved: Made kgdb ignore this particular die notification (cmd == DIE_PAGE_FAULT) in its handler. I request you to merge this patch to the main line community . If any questions please contact me at sshaiju@mvista.com (shaiju_sada@yahoo.com) Regards, shaiju --001a11c1ec1629fc4c0500622092 Content-Type: application/octet-stream; name="4995-kgdb-Ignore-DIE_PAGE_FAULT-event-in-notify-handler.patch" Content-Disposition: attachment; filename="4995-kgdb-Ignore-DIE_PAGE_FAULT-event-in-notify-handler.patch" Content-Transfer-Encoding: base64 X-Attachment-Id: bf796e2c278abca9_0.1 RnJvbSAwNTZjYWE5OTkxNTEyNzA0Y2IzOWY2NTgyOGUxZmZlYTQ3ODMwYzZjIE1vbiBTZXAgMTcg MDA6MDA6MDAgMjAwMQpGcm9tOiBzYWRhc2l2YW4gc2hhaWp1IDxzaGFpanVAbG9jYWxob3N0Lmxv Y2FsZG9tYWluPgpEYXRlOiBXZWQsIDI3IEp1bCAyMDExIDE0OjU0OjM5IC0wNzAwClN1YmplY3Q6 IFtQQVRDSF0ga2dkYjogSWdub3JlIERJRV9QQUdFX0ZBVUxUIGV2ZW50IGluIG5vdGlmeSBoYW5k bGVyCgpTb3VyY2U6IE1vbnRhVmlzdGEgU29mdHdhcmUsIExMQwpNUjogNDUyODAKVHlwZTogRGVm ZWN0IEZpeApEaXNwb3NpdGlvbjogTmVlZHMgc3VibWl0dGluZyB0byBrZXJuZWwub3JnCkNoYW5n ZUlEOiA1YmVjMDlmN2VjMGE0Nzc1MTY5ZjVjYmExNjk3NmJjM2E2YjQ1NTk4CkRlc2NyaXB0aW9u OgoKSWdub3JlIG5vdGlmeV9kaWUoKSBmcm9tIGRvX3BhZ2VmYXVsdCgpLCBpbiBrZ2RiJ3MgcmVn aXN0ZXJfZGllX25vdGlmaWVyKCkKaGFuZGxlcgoKU2lnbmVkLW9mZi1ieTogU2FkYXNpdmFuIDxz c2hhaWp1QG12aXN0YS5jb20+ClNpZ25lZC1vZmYtYnk6IERhbGUgRmFybnN3b3J0aCA8ZGZhcm5z d29ydGhAbXZpc3RhLmNvbT4KLS0tCiBhcmNoL21pcHMva2VybmVsL2tnZGIuYyB8ICAgIDUgKysr KysKIDEgZmlsZXMgY2hhbmdlZCwgNSBpbnNlcnRpb25zKCspLCAwIGRlbGV0aW9ucygtKQoKZGlm ZiAtLWdpdCBhL2FyY2gvbWlwcy9rZXJuZWwva2dkYi5jIGIvYXJjaC9taXBzL2tlcm5lbC9rZ2Ri LmMKaW5kZXggNTBjOWJiOC4uM2U0YWUzMSAxMDA2NDQKLS0tIGEvYXJjaC9taXBzL2tlcm5lbC9r Z2RiLmMKKysrIGIvYXJjaC9taXBzL2tlcm5lbC9rZ2RiLmMKQEAgLTE5MSw2ICsxOTEsMTEgQEAg c3RhdGljIGludCBrZ2RiX21pcHNfbm90aWZ5KHN0cnVjdCBub3RpZmllcl9ibG9jayAqc2VsZiwg dW5zaWduZWQgbG9uZyBjbWQsCiAJc3RydWN0IHB0X3JlZ3MgKnJlZ3MgPSBhcmdzLT5yZWdzOwog CWludCB0cmFwID0gKHJlZ3MtPmNwMF9jYXVzZSAmIDB4N2MpID4+IDI7CiAKKyAgICAgICAgLyog aWdub3JlIHRoZSBub3RpZnlfZGllKCkgZnJvbSBkb19wYWdlX2ZhdWx0KCksIHdoaWNoIGlzIG1l YW50IGZvciBrcHJvYmVzICovCisKKwlpZihjbWQgPT0gRElFX1BBR0VfRkFVTFQpCisJCXJldHVy biBOT1RJRllfRE9ORTsgICAgICAgCisKIAkvKiBVc2VycGFjZSBldmVudHMsIGlnbm9yZS4gKi8K IAlpZiAodXNlcl9tb2RlKHJlZ3MpKQogCQlyZXR1cm4gTk9USUZZX0RPTkU7Ci0tIAoxLjcuMC4x Cgo= --001a11c1ec1629fc4c0500622092--