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path: root/arch/i386/kernel/cpu/mtrr/main.c
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2007-05-02[PATCH] x86: Save the MTRRs of the BSP before booting an APBernhard Kaindl
Applied fix by Andew Morton: http://lkml.org/lkml/2007/4/8/88 - Fix `make headers_check'. AMD and Intel x86 CPU manuals state that it is the responsibility of system software to initialize and maintain MTRR consistency across all processors in Multi-Processing Environments. Quote from page 188 of the AMD64 System Programming manual (Volume 2): 7.6.5 MTRRs in Multi-Processing Environments "In multi-processing environments, the MTRRs located in all processors must characterize memory in the same way. Generally, this means that identical values are written to the MTRRs used by the processors." (short omission here) "Failure to do so may result in coherency violations or loss of atomicity. Processor implementations do not check the MTRR settings in other processors to ensure consistency. It is the responsibility of system software to initialize and maintain MTRR consistency across all processors." Current Linux MTRR code already implements the above in the case that the BIOS does not properly initialize MTRRs on the secondary processors, but the case where the fixed-range MTRRs of the boot processor are changed after Linux started to boot, before the initialsation of a secondary processor, is not handled yet. In this case, secondary processors are currently initialized by Linux with MTRRs which the boot processor had very early, when mtrr_bp_init() did run, but not with the MTRRs which the boot processor uses at the time when that secondary processors is actually booted, causing differing MTRR contents on the secondary processors. Such situation happens on Acer Ferrari 1000 and 5000 notebooks where the BIOS enables and sets AMD-specific IORR bits in the fixed-range MTRRs of the boot processor when it transitions the system into ACPI mode. The SMI handler of the BIOS does this in SMM, entered while Linux ACPI code runs acpi_enable(). Other occasions where the SMI handler of the BIOS may change bits in the MTRRs could occur as well. To initialize newly booted secodary processors with the fixed-range MTRRs which the boot processor uses at that time, this patch saves the fixed-range MTRRs of the boot processor before new secondary processors are started. When the secondary processors run their Linux initialisation code, their fixed-range MTRRs will be updated with the saved fixed-range MTRRs. If CONFIG_MTRR is not set, we define mtrr_save_state as an empty statement because there is nothing to do. Possible TODOs: *) CPU-hotplugging outside of SMP suspend/resume is not yet tested with this patch. *) If, even in this case, an AP never runs i386/do_boot_cpu or x86_64/cpu_up, then the calls to mtrr_save_state() could be replaced by calls to mtrr_save_fixed_ranges(NULL) and mtrr_save_state() would not be needed. That would need either verification of the CPU-hotplug code or at least a test on a >2 CPU machine. *) The MTRRs of other running processors are not yet checked at this time but it might be interesting to syncronize the MTTRs of all processors before booting. That would be an incremental patch, but of rather low priority since there is no machine known so far which would require this. AK: moved prototypes on x86-64 around to fix warnings Signed-off-by: Bernhard Kaindl <bk@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Andi Kleen <ak@suse.de> Cc: Dave Jones <davej@codemonkey.org.uk>
2007-02-13[PATCH] i386: fix size_or_mask and size_and_maskAndreas Herrmann
mtrr: fix size_or_mask and size_and_mask This fixes two bugs in /proc/mtrr interface: o If physical address size crosses the 44 bit boundary size_or_mask is evaluated wrong. o size_and_mask limits width of physical base address for an MTRR to be less than 44 bits. TBD: later patch had one more change, but I think that was bogus. TBD: need to double check Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07[PATCH] x86-64: replace kmalloc+memset with kzalloc in MTRR codeBurman Yan
Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07[PATCH] i386: fix MTRR codeJan Beulich
Until not so long ago, there were system log messages pointing to inconsistent MTRR setup of the video frame buffer caused by the way vesafb and X worked. While vesafb was fixed meanwhile, I believe fixing it there only hides a shortcoming in the MTRR code itself, in that that code is not symmetric with respect to the ordering of attempts to set up two (or more) regions where one contains the other. In the current shape, it permits only setting up sub-regions of pre-exisiting ones. The patch below makes this symmetric. While working on that I noticed a few more inconsistencies in that code, namely - use of 'unsigned int' for sizes in many, but not all places (the patch is converting this to use 'unsigned long' everywhere, which specifically might be necessary for x86-64 once a processor supporting more than 44 physical address bits would become available) - the code to correct inconsistent settings during secondary processor startup tried (if necessary) to correct, among other things, the value in IA32_MTRR_DEF_TYPE, however the newly computed value would never get used (i.e. stored in the respective MSR) - the generic range validation code checked that the end of the to-be-added range would be above 1MB; the value checked should have been the start of the range - when contained regions are detected, previously this was allowed only when the old region was uncacheable; this can be symmetric (i.e. the new region can also be uncacheable) and even further as per Intel's documentation write-trough and write-back for either region is also compatible with the respective opposite in the other Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07[PATCH] i386: conditionalize inclusion of some MTRR flavorsJan Beulich
Avoid inclusion of code that's dead for x86-64. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07[PATCH] i386: fix buggy MTRR address checksAndreas Mohr
Fix checks that failed to realize that values are 4-kB-unit-sized (note the format strings in this same diff context which *do* realize the unit size, via appended "000"!). Also fix an incorrect below-1MB area check (as gathered from Jan Beulich's unapplied patch at http://www.ussg.iu.edu/hypermail/linux/kernel/0411.1/1378.html ) Update mtrr_add_page() docu to make 4-kB-sized calculation more obvious. Given several further items mentioned in Jan's patch mail, all in all MTRR code seems surprisingly buggy, for a surprisingly long period of time (many years). Further work/investigation would be useful. TBD Note that my patch is pretty much UNTESTED, since I can only verify that it TBD successfully boots my machine, but I cannot test against actual buggy TBD hardware which would require these (formerly broken) checks. Long -mm TBD simmering would make sense, especially since these now-working checks might TBD turn out to have adverse effects on unaffected hardware. Signed-off-by: Andreas Mohr <andi@lisas.de> Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-03-26[PATCH] sem2mutex: misc static one-file mutexesIngo Molnar
Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jens Axboe <axboe@suse.de> Cc: Neil Brown <neilb@cse.unsw.edu.au> Acked-by: Alasdair G Kergon <agk@redhat.com> Cc: Greg KH <greg@kroah.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Adam Belay <ambx1@neo.rr.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-05[X86] Remove pointless versioning of mtrr driver.Dave Jones
It's not like this has changed significantly, and probably never will. Reduce some bootup dmesg noise. Signed-off-by: Dave Jones <davej@redhat.com>
2005-12-20[X86] Rename MTRR mutex to something more sensible.Dave Jones
I spotted 'main_lock' whilst grovelling through a vmlinux with objdump. Even if it is static, it's a horrible name. Signed-off-by: Dave Jones <davej@redhat.com>
2005-11-14[PATCH] x86_64: Force correct address space size for MTRR on some 64bit ↵Shaohua Li
Intel Xeons They report 40bit, but only have 36bits of physical address space. This caused problems with setting up the correct masks for MTRR. CPUID workaround for steppings 0F33h(supporting x86) and 0F34h(supporting x86 and EM64T). Detail info can be found at: http://download.intel.com/design/Xeon/specupdt/30240216.pdf http://download.intel.com/design/Pentium4/specupdt/30235221.pdf Signed-off-by: Shaohua Li<shaohua.li@intel.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05[PATCH] swsusp: fix remaining u32 vs. pm_message_t confusionPavel Machek
Fix remaining bits of u32 vs. pm_message confusion. Should not break anything. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07[PATCH] MTRR suspend/resume cleanupShaohua Li
There has been some discuss about solving the SMP MTRR suspend/resume breakage, but I didn't find a patch for it. This is an intent for it. The basic idea is moving mtrr initializing into cpu_identify for all APs (so it works for cpu hotplug). For BP, restore_processor_state is responsible for restoring MTRR. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Acked-by: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] mtrr size-and-base debuggingAndrew Morton
Consolidate the mtrr sanity checking, add a dump_stack(). Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] Enable write combining for server works LE rev > 6Lee Revell
Enable write combining for server works LE rev > 6 per http://www.ussg.iu.edu/hypermail/linux/kernel/0104.3/1007.html Signed-Off-By: Lee Revell <rlrevell@joe-job.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16[PATCH] x86_64: Always use CPUID 80000008 to figure out MTRR address space sizeAndi Kleen
It doesn't make sense to only do this only for AMD K8. This would support future CPUs with extended address spaces properly. For i386 and x86-64 Cc: <davej@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!