From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: From: Viju Subject: RE: can i call copy_to_user with interrupts masked Date: Mon, 27 Aug 2001 20:39:18 +0530 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Sender: owner-linux-mm@kvack.org Return-Path: To: PRASENJIT CHAKRABORTY , linux-mm@kvack.org Cc: arund@bellatlantic.net List-ID: At a high level OS point of view that cannot be the cause i would say. When u access a page, the processor finds that the address is not mapped in the page tables, it suspends the execution of the current process and generates a page_fault. The OS is supposed to handle the page_fault and it finds the corresponding page in the backing store and faults the page in. After a transaction entry is made inthe page tables for the newly faulted in page, it returns. The processor starts excuting the same statement at which it stopped and the process resumes normal execution. I would say find what do_page_fault is returning, it shud return an error if it couldnt find the page for some reason.(Like illegal access or couldnt swap the page in). If the page_fault is returning error then finding out y it is retuning that error might solve ur problem. Thnx, Viju. -----Original Message----- From: PRASENJIT CHAKRABORTY [mailto:pras_chakra@yahoo.com] Sent: Monday, August 27, 2001 8:27 PM To: linux-mm@kvack.org Cc: arund@bellatlantic.net Subject: can i call copy_to_user with interrupts masked Hello All, This is in continuation with my previous mail. While debugging I've noticed that __copy_to_user() fails when I stop the Bottom Half before the call to __copy_to_user(), so if the page in not currently mapped then it forbids do_page_fault() to get invoked and hence the failure. So I would like to know whether this hypothesis is right or not? And if not then the possible explanation. Thankx Prasenjit __________________________________________________ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/