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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SA1PR11MB6734.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: b7fed83f-e752-492d-e75c-08db29a11c8d X-MS-Exchange-CrossTenant-originalarrivaltime: 21 Mar 2023 00:13:34.8123 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: yRFkVqtMDNz2sW3QQzQl5yAbwr8zjC9lJpV4+cv1nA76fZ1tPlLxaXFo4oGsZsdb9fpcH0LY37Zgq7BZZ4E40Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR11MB6826 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > The purpose of separate stacks for NMI, #DB and #MC *in the kernel* > > (remember that user space faults are always taken on stack level 0) is > > to avoid overflowing the kernel stack. #DB in the kernel would imply > > the use of a kernel debugger. >=20 > Perf (and through it bpf) also has access to #DB. They can set > breakpoints on kernel instructions/memory just fine provided permission > etc. So they are still *kernel* debuggers :)