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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: c08caaa0-081c-4b51-b457-08db299fe268 X-MS-Exchange-CrossTenant-originalarrivaltime: 21 Mar 2023 00:04:47.7952 (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: aVlduY+/6m/Z4eG3H9CsEAveftFCv+opccqiMhAe3CKsID3hPVgYRntUn1T/wrXyvtGgdd98HhK3LZ1r8vzRHg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO6PR11MB5587 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > Unlike IDT, no need to save/restore dr7 in FRED machine check handler. >=20 > Given how fragile MCE is, the question should be, do we ever want hw > breakpoints to happen while it is running? HW breakpoints still work if they are properly configured. > If the hw-breakpoint handler trips on the same memory fail that got us in= to the > mce the first time, we're dead. Right. Unless the MCIP bit is turned off any subsequent #MC goes to shutdown ("machine is screwed"). It's the kernel debugger's responsibility to decide how to proceed in such cases. But if the kernel debugger itself is in a screwed memory region, we are soooooo dead. Thanks! Xin