similar to: [PATCH] turn off writable page tables

I want to know any difference between writing, reading and shadow page table (for example performance). I am thankful for any help or resource for that. -- Best Regards Mohamad Taghi Mir Mohamad Rezaie Iran University of Science and Technology Department of Computer Science & Engineering System Software Group _______________________________________________ Xen-devel mailing list

hi, I''m developing my own 32-bit (no PAE) paravirtualized kernel for xen with Mini-OS as a starting point. I am currently working on process page table support (equivalent of arch/i386/mm/pgtable-xen.c) and mostly following Linux for the moment. I noticed that linux-2.6.18-xen never pins an L1 table (a pte), yet __pgd_pin() walks the page directory and gives up write access on the kernel

hi, what''s the best way (if at all) to iterate through all of a domain''s page tables within xen 2.0.6? i need to find all references to a specific pte value (which is a given). essentially, a reverse page-table lookup. i''m hesitant to switch to 3.0, but if it''s easier to do what i want, just let me know. thanks, -A. -- Aaron Marks Distributed Systems Lab

In xen 3.0.4-1 source, where is the *unhook/rehook page table implementation* which is important things in ''writable page table mode''.? I can''t find it. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel

The patch deals with the situation which guest OS uses unused page table pages as data pages and write data to them. The pages will still be grabbed by Xen as page table pages, and lots of unnecessary page faults occur. The patch will check if the data guest writes to the page table contains valid mfn or not, if not, we believe it is a data page now and then unshadow the page. The patch

The goal for this series is to introduce the hmm_range_fault() output array flags HMM_PFN_PMD and HMM_PFN_PUD. This allows a device driver to know that a given 4K PFN is actually mapped by the CPU using either a PMD sized or PUD sized CPU page table entry and therefore the device driver can safely map system memory using larger device MMU PTEs. The series is based on 5.8.0-rc3 and is intended for

[ REPOST: Apologies to anyone who has seen this before. It didn't make it onto any of the lists it should have. -J ] Hi Andrew, This series of patches lays the basic ground work for the paravirtualized kernel patches coming later on. I think this lot is ready for the rough-and-tumble world of the -mm tree. For the most part, these patches do nothing or very little. The patches should

[ REPOST: Apologies to anyone who has seen this before. It didn't make it onto any of the lists it should have. -J ] Hi Andrew, This series of patches lays the basic ground work for the paravirtualized kernel patches coming later on. I think this lot is ready for the rough-and-tumble world of the -mm tree. For the most part, these patches do nothing or very little. The patches should

Hi all, This little series adds a new transaction-like abstraction for doing RMW updates to a pte, hooks it into paravirt_ops, and then makes use of it in Xen. The basic problem is that mprotect is very slow under Xen (up to 50x slower than native), primarily because of the ptent = ptep_get_and_clear(mm, addr, pte); ptent = pte_modify(ptent, newprot); /* ... */ set_pte_at(mm, addr, pte,

Hi all, This little series adds a new transaction-like abstraction for doing RMW updates to a pte, hooks it into paravirt_ops, and then makes use of it in Xen. The basic problem is that mprotect is very slow under Xen (up to 50x slower than native), primarily because of the ptent = ptep_get_and_clear(mm, addr, pte); ptent = pte_modify(ptent, newprot); /* ... */ set_pte_at(mm, addr, pte,

Hi all, This little series adds a new transaction-like abstraction for doing RMW updates to a pte, hooks it into paravirt_ops, and then makes use of it in Xen. The basic problem is that mprotect is very slow under Xen (up to 50x slower than native), primarily because of the ptent = ptep_get_and_clear(mm, addr, pte); ptent = pte_modify(ptent, newprot); /* ... */ set_pte_at(mm, addr, pte,

The ptep_establish macro is only used on user-level PTEs, for P->P mapping changes. Since these always happen under protection of the pagetable lock, the strong synchronization of a 64-bit cmpxchg is not needed, in fact, not even a lock prefix needs to be used. We can simply instead clear the P-bit, followed by a normal set. The write ordering is still important to avoid the possibility of

The goal for this series is to introduce the hmm_pfn_to_map_order() function. This allows a device driver to know that a given 4K PFN is actually mapped by the CPU using a larger sized CPU page table entry and therefore the device driver can safely map system memory using larger device MMU PTEs. The series is based on 5.8.0-rc3 and is intended for Jason Gunthorpe's hmm tree. These were

Hi Andi, Here's a repost of the paravirt_ops update series I posted the other day. Since then, I found a few potential bugs with patching clobbering, cleaned up and documented paravirt.h and the patching machinery. Overview: add-MAINTAINERS.patch obvious remove-CONFIG_DEBUG_PARAVIRT.patch No longer meaningful or needed. paravirt-nop.patch Clean up nop paravirt_ops functions, mainly to

Hi Andi, Here's a repost of the paravirt_ops update series I posted the other day. Since then, I found a few potential bugs with patching clobbering, cleaned up and documented paravirt.h and the patching machinery. Overview: add-MAINTAINERS.patch obvious remove-CONFIG_DEBUG_PARAVIRT.patch No longer meaningful or needed. paravirt-nop.patch Clean up nop paravirt_ops functions, mainly to

From: Martin Schwidefsky <schwidefsky at de.ibm.com> The SIE instruction on s390 uses the 2nd half of the page table page to virtualize the storage keys of a guest. This patch offers the s390_enable_sie function, which reorganizes the page tables of a single-threaded process to reserve space in the page table: s390_enable_sie makes sure that the process is single threaded and then uses

Hi all, [ Change since last post: change name to ptep_modify_prot_, on the grounds that it isn't really a general pte-modification interface. ] This little series adds a new transaction-like abstraction for doing RMW updates to a pte, hooks it into paravirt_ops, and then makes use of it in Xen. The basic problem is that mprotect is very slow under Xen (up to 50x slower than native),

Hi all, [ Change since last post: change name to ptep_modify_prot_, on the grounds that it isn't really a general pte-modification interface. ] This little series adds a new transaction-like abstraction for doing RMW updates to a pte, hooks it into paravirt_ops, and then makes use of it in Xen. The basic problem is that mprotect is very slow under Xen (up to 50x slower than native),

Hi all, [ Change since last post: change name to ptep_modify_prot_, on the grounds that it isn't really a general pte-modification interface. ] This little series adds a new transaction-like abstraction for doing RMW updates to a pte, hooks it into paravirt_ops, and then makes use of it in Xen. The basic problem is that mprotect is very slow under Xen (up to 50x slower than native),

Is pte_offset_map allowed to happen within lazy mmu? I presume not, because you definitely don't want the mapping pte update to be deferred. Or, more specifically, is kunmap_atomic ever allowed within lazy mmu? I'm looking at kpte_clear_flush; I've already got a patch which turns this into a pv_op, along with a Xen implementation. But I think its probably an excess pv_op for a