From: Andi Kleen <ak@suse.de>
To: "Jan Beulich" <jbeulich@novell.com>
Cc: linux-kernel@vger.kernel.org, patches@x86-64.org
Subject: Re: [patches] [PATCH] [13/50] x86: Fix and reenable CLFLUSH support inchange_page_attr()
Date: Mon, 1 Oct 2007 12:38:10 +0200 [thread overview]
Message-ID: <200710011238.10318.ak@suse.de> (raw)
In-Reply-To: <46F79021.76E4.0078.0@novell.com>
On Monday 24 September 2007 10:23:29 Jan Beulich wrote:
> >@@ -162,7 +198,7 @@ __change_page_attr(unsigned long address
> > /* on x86-64 the direct mapping set at boot is not using 4k pages */
> > BUG_ON(PageReserved(kpte_page));
> >
> >- save_page(kpte_page);
> >+ save_page(kpte_page, 0);
> > if (page_private(kpte_page) == 0)
> > revert_page(address, ref_prot);
> > return 0;
>
> What is the point of continuing to launder kpte_page here? Page table pages
> never get their caching attributes changed, nor would their direct mapping
> ever change. (Same for i386, obviously.)
We can only free the page table after all the TLBs have been flushed;
otherwise other CPUs can walk already overwritten data as page tables (which can
then cause various problems). This is similar to the lazy TLB flush logic in the
standard VM.
We don't need to cache flush it though, that is why 0 is passed here.
Admittedly the function argument is a little bogus because the caller
could just do it; didn't change that yet.
-Andi
next prev parent reply other threads:[~2007-10-01 10:38 UTC|newest]
Thread overview: 105+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-21 22:31 [PATCH] [0/50] x86 2.6.24 patches review II Andi Kleen
2007-09-21 22:31 ` [PATCH] [1/50] x86_64: store core id bits in cpuinfo_x8 Andi Kleen
2007-09-21 22:31 ` [PATCH] [2/50] x86_64: use core id bits for apicid_to_node initialization Andi Kleen
2007-09-21 22:32 ` [PATCH] [3/50] x86_64: remove never used apic_mapped Andi Kleen
2007-09-21 22:32 ` [PATCH] [4/50] x86: add cpu codenames for Kconfig.cpu Andi Kleen
2007-09-21 22:45 ` Dave Jones
2007-09-21 23:52 ` Alan Cox
2007-09-22 6:57 ` Sam Ravnborg
2007-09-22 9:46 ` Jan Engelhardt
2007-09-22 14:23 ` Dave Jones
2007-09-22 17:40 ` Randy Dunlap
2007-09-30 10:09 ` Andi Kleen
2007-09-22 17:50 ` Thomas Gleixner
2007-10-01 11:17 ` Andi Kleen
2007-09-21 22:32 ` [PATCH] [5/50] i386: change order in Kconfig.cpu Andi Kleen
2007-09-21 22:32 ` [PATCH] [6/50] i386: clean up oops/bug reports Andi Kleen
2007-09-21 22:41 ` Chuck Ebbert
2007-09-22 9:47 ` Jan Engelhardt
2007-09-22 2:51 ` Killing printk calls for size (Re: [PATCH] [6/50] i386: clean up oops/bug reports) Oleg Verych
2007-09-21 22:32 ` [PATCH] [7/50] x86: expand /proc/interrupts to include missing vectors, v2 Andi Kleen
2007-09-22 3:35 ` possible corrections in the docs (Re: [PATCH] [7/50] x86: expand /proc/interrupts to include missing vectors, v2) Oleg Verych
2007-09-22 3:52 ` Joe Korty
2007-09-21 22:32 ` [PATCH] [8/50] x86_64: remove x86_cpu_to_log_apicid Andi Kleen
2007-09-21 22:32 ` [PATCH] [9/50] i386: validate against ACPI motherboard resources Andi Kleen
2007-09-22 6:49 ` Yinghai Lu
2007-09-22 6:56 ` Yinghai Lu
2007-09-22 16:28 ` Robert Hancock
2007-09-22 18:01 ` Thomas Gleixner
2007-09-22 18:42 ` Robert Hancock
2007-09-22 20:40 ` Yinghai Lu
2007-09-22 20:56 ` H. Peter Anvin
2007-09-22 21:27 ` Robert Hancock
2007-09-23 1:20 ` Yinghai Lu
2007-09-23 1:34 ` Yinghai Lu
2007-09-22 20:47 ` Yinghai Lu
2007-09-21 22:32 ` [PATCH] [10/50] x86_64: install unstripped copies of compat vdso on disk Andi Kleen
2007-09-21 22:32 ` [PATCH] [11/50] x86_64: Install unstripped copy of 64bit vdso to disk Andi Kleen
2007-09-21 22:32 ` [PATCH] [12/50] x86_64: Untable __init references between IO data Andi Kleen
2007-09-22 5:37 ` [patches] " Yinghai Lu
2007-09-21 22:32 ` [PATCH] [13/50] x86: Fix and reenable CLFLUSH support in change_page_attr() Andi Kleen
2007-09-22 5:47 ` Oleg Verych
2007-10-01 10:59 ` Andi Kleen
2007-09-24 8:23 ` [patches] [PATCH] [13/50] x86: Fix and reenable CLFLUSH support inchange_page_attr() Jan Beulich
2007-10-01 10:38 ` Andi Kleen [this message]
2007-09-21 22:32 ` [PATCH] [14/50] x86: Minor code-style cleanups to change_page_attr Andi Kleen
2007-09-21 22:32 ` [PATCH] [15/50] x86_64: Return EINVAL for unknown address in change_page_attr Andi Kleen
2007-09-24 8:32 ` [patches] [PATCH] [15/50] x86_64: Return EINVAL for unknown addressin change_page_attr Jan Beulich
2007-09-21 22:32 ` [PATCH] [16/50] x86: Use macros to modify the PG_arch_1 page flags in change_page_attr Andi Kleen
2007-09-21 22:32 ` [PATCH] [17/50] x86_64: remove STR() macros Andi Kleen
2007-09-21 22:32 ` [PATCH] [18/50] x86_64: Save registers in saved_context during suspend and hibernation Andi Kleen
2007-09-21 22:32 ` [PATCH] [19/50] Experimental: detect if SVM is disabled by BIOS Andi Kleen
2007-09-22 6:59 ` Sam Ravnborg
2007-09-22 9:17 ` Joerg Roedel
2007-10-01 16:47 ` Andi Kleen
2007-10-01 20:12 ` Joerg Roedel
2007-10-01 21:45 ` [patches] " Andi Kleen
2007-10-01 22:13 ` Joerg Roedel
2007-09-22 19:05 ` Thomas Gleixner
2007-09-21 22:32 ` [PATCH] [20/50] x86_64: Fix some broken white space in arch/x86_64/mm/init.c Andi Kleen
2007-09-22 19:17 ` Thomas Gleixner
2007-09-23 1:47 ` Oleg Verych
2007-09-21 22:32 ` [PATCH] [21/50] i386: Misc cpuinit annotations Andi Kleen
2007-09-21 22:32 ` [PATCH] [22/50] " Andi Kleen
2007-09-21 22:32 ` [PATCH] [23/50] x86_64: Implement missing x86_64 function smp_call_function_mask() Andi Kleen
2007-09-21 22:32 ` [PATCH] [24/50] x86_64: Eliminate result signage problem in asm-x86_64/bitops.h Andi Kleen
2007-09-21 22:32 ` [PATCH] [25/50] x86_64: Add parenthesis to IRQ vector macros Andi Kleen
2007-09-21 22:32 ` [PATCH] [26/50] i386: export i386 smp_call_function_mask() to modules Andi Kleen
2007-09-21 22:32 ` [PATCH] [27/50] x86_64: Remove duplicated vsyscall nsec update Andi Kleen
2007-09-21 22:32 ` [PATCH] [28/50] i386: remove stub early_printk.c Andi Kleen
2007-09-21 22:32 ` [PATCH] [29/50] x86: honor _PAGE_PSE bit on page walks Andi Kleen
2007-09-21 22:32 ` [PATCH] [30/50] x86_64: remove some dead code Andi Kleen
2007-09-21 22:32 ` [PATCH] [31/50] x86_64: honor notify_die() returning NOTIFY_STOP Andi Kleen
2007-09-22 19:23 ` Thomas Gleixner
2007-09-21 22:32 ` [PATCH] [32/50] x86: Show last exception from/to register contents Andi Kleen
2007-09-21 22:32 ` [PATCH] [33/50] x86: rename .i assembler includes to .h Andi Kleen
2007-09-21 22:32 ` [PATCH] [34/50] i386: Fix argument signedness warnings Andi Kleen
2007-09-22 5:06 ` Satyam Sharma
2007-09-22 10:01 ` Jan Engelhardt
2007-09-22 17:42 ` Randy Dunlap
2007-09-21 22:32 ` [PATCH] [35/50] i386: Do cpuid_device_create() in CPU_UP_PREPARE instead of CPU_ONLINE Andi Kleen
2007-09-22 19:33 ` Thomas Gleixner
2007-09-23 1:52 ` Akinobu Mita
2007-09-23 7:52 ` Thomas Gleixner
2007-09-21 22:32 ` [PATCH] [36/50] x86: Use raw locks during oopses Andi Kleen
2007-09-21 22:32 ` [PATCH] [37/50] x86_64: Clean up mce= argument parsing slightly Andi Kleen
2007-09-21 22:32 ` [PATCH] [38/50] x86_64: fix off-by-one in find_next_zero_string Andi Kleen
2007-09-21 22:32 ` [PATCH] [39/50] i386: fix 4 bit apicid assumption of mach-default Andi Kleen
2007-09-21 22:32 ` [PATCH] [40/50] i386: Fix section mismatch Andi Kleen
2007-09-21 22:32 ` [PATCH] [41/50] i386: fix section mismatch warning in intel.c Andi Kleen
2007-09-21 22:32 ` [PATCH] [42/50] i386: constify wd_ops Andi Kleen
2007-09-21 22:32 ` [PATCH] [43/50] x86: multi-byte single instruction NOPs Andi Kleen
2007-09-21 22:32 ` [PATCH] [44/50] i386: Introduce "used_vectors" bitmap which can be used to reserve vectors Andi Kleen
2007-09-21 22:32 ` [PATCH] [45/50] x86_64: configure HPET_EMULATE_RTC automatically Andi Kleen
2007-09-21 22:32 ` [PATCH] [46/50] x86: also show non-zero IRQ counts for vectors that currently don't have a handler Andi Kleen
2007-09-21 22:32 ` [PATCH] [47/50] i386: avoid temporarily inconsistent pte-s Andi Kleen
2007-09-21 22:32 ` [PATCH] [48/50] x86_64: return correct error code from child_rip in x86_64 entry.S Andi Kleen
2007-09-21 22:32 ` [PATCH] [49/50] x86_64: Initialize 64bit registers for a.out executables Andi Kleen
2007-09-21 22:32 ` [PATCH] [50/50] x86_64: Remove fpu io port resource Andi Kleen
2007-09-21 23:00 ` Jeff Garzik
2007-10-01 10:40 ` Andi Kleen
2007-10-01 11:30 ` Jeff Garzik
2007-10-01 11:48 ` Andi Kleen
2007-10-01 13:33 ` Jeff Garzik
2007-10-01 14:16 ` Mark Lord
2007-10-02 14:37 ` Alan Cox
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