- 12 10月, 2010 1 次提交
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由 Yinghai Lu 提交于
Russ reported SGI UV is broken recently. He said: | The SRAT table shows that memory range is spread over two nodes. | | SRAT: Node 0 PXM 0 100000000-800000000 | SRAT: Node 1 PXM 1 800000000-1000000000 | SRAT: Node 0 PXM 0 1000000000-1080000000 | |Previously, the kernel early_node_map[] would show three entries |with the proper node. | |[ 0.000000] 0: 0x00100000 -> 0x00800000 |[ 0.000000] 1: 0x00800000 -> 0x01000000 |[ 0.000000] 0: 0x01000000 -> 0x01080000 | |The problem is recent community kernel early_node_map[] shows |only two entries with the node 0 entry overlapping the node 1 |entry. | | 0: 0x00100000 -> 0x01080000 | 1: 0x00800000 -> 0x01000000 After looking at the changelog, Found out that it has been broken for a while by following commit |commit 8716273c |Author: David Rientjes <rientjes@google.com> |Date: Fri Sep 25 15:20:04 2009 -0700 | | x86: Export srat physical topology Before that commit, register_active_regions() is called for every SRAT memory entry right away. Use nodememblk_range[] instead of nodes[] in order to make sure we capture the actual memory blocks registered with each node. nodes[] contains an extended range which spans all memory regions associated with a node, but that does not mean that all the memory in between are included. Reported-by: NRuss Anderson <rja@sgi.com> Tested-by: NRuss Anderson <rja@sgi.com> Signed-off-by: NYinghai Lu <yinghai@kernel.org> LKML-Reference: <4CB27BDF.5000800@kernel.org> Acked-by: NDavid Rientjes <rientjes@google.com> Cc: <stable@kernel.org> 2.6.33 .34 .35 .36 Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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- 11 10月, 2010 3 次提交
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由 Zachary Amsden 提交于
The VMCB is reset whenever we receive a startup IPI, so Linux is setting TSC back to zero happens very late in the boot process and destabilizing the TSC. Instead, just set TSC to zero once at VCPU creation time. Why the separate patch? So git-bisect is your friend. Signed-off-by: NZachary Amsden <zamsden@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Zachary Amsden 提交于
On reset, VMCB TSC should be set to zero. Instead, code was setting tsc_offset to zero, which passes through the underlying TSC. Signed-off-by: NZachary Amsden <zamsden@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Borislav Petkov 提交于
This fixes possible cases of not collecting valid error info in the MCE error thresholding groups on F10h hardware. The current code contains a subtle problem of checking only the Valid bit of MSR0000_0413 (which is MC4_MISC0 - DRAM thresholding group) in its first iteration and breaking out if the bit is cleared. But (!), this MSR contains an offset value, BlkPtr[31:24], which points to the remaining MSRs in this thresholding group which might contain valid information too. But if we bail out only after we checked the valid bit in the first MSR and not the block pointer too, we miss that other information. The thing is, MC4_MISC0[BlkPtr] is not predicated on MCi_STATUS[MiscV] or MC4_MISC0[Valid] and should be checked prior to iterating over the MCI_MISCj thresholding group, irrespective of the MC4_MISC0[Valid] setting. Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com> Cc: <stable@kernel.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 08 10月, 2010 1 次提交
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由 Jin Dongming 提交于
When the feature PTS is not supported by CPU, the sysfile package_power_limit_count for package should not be generated. This patch is used for fixing missing { and }. The patch is not complete as there are other error handling problems in this function - but that can wait until the merge window. Signed-off-by: NJin Dongming <jin.dongming@np.css.fujitsu.com> Reviewed-by: NFenghua Yu <fenghua.yu@initel.com> Acked-by: NJean Delvare <khali@linux-fr.org> Cc: Brown Len <len.brown@intel.com> Cc: Guenter Roeck <guenter.roeck@ericsson.com> Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: lm-sensors@lm-sensors.org <lm-sensors@lm-sensors.org> LKML-Reference: <4C7625D1.4060201@np.css.fujitsu.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 06 10月, 2010 1 次提交
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由 Linus Torvalds 提交于
With all the recent module loading cleanups, we've minimized the code that sits under module_mutex, fixing various deadlocks and making it possible to do most of the module loading in parallel. However, that whole conversion totally missed the rather obscure code that adds a new module to the list for BUG() handling. That code was doubly obscure because (a) the code itself lives in lib/bugs.c (for dubious reasons) and (b) it gets called from the architecture-specific "module_finalize()" rather than from generic code. Calling it from arch-specific code makes no sense what-so-ever to begin with, and is now actively wrong since that code isn't protected by the module loading lock any more. So this commit moves the "module_bug_{finalize,cleanup}()" calls away from the arch-specific code, and into the generic code - and in the process protects it with the module_mutex so that the list operations are now safe. Future fixups: - move the module list handling code into kernel/module.c where it belongs. - get rid of 'module_bug_list' and just use the regular list of modules (called 'modules' - imagine that) that we already create and maintain for other reasons. Reported-and-tested-by: NThomas Gleixner <tglx@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Adrian Bunk <bunk@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@kernel.org Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 05 10月, 2010 1 次提交
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由 Stefano Stabellini 提交于
if !xen_have_vector_callback do not initialize PV timer unconditionally because we still don't know how many cpus are available and if there is more than one we won't be able to receive the timer interrupts on cpu > 0. This patch fixes an hang at boot when Xen does not support vector callbacks and the guest has multiple vcpus. Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: NJeremy Fitzhardinge <jeremy@goop.org>
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- 01 10月, 2010 4 次提交
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由 Thomas Gleixner 提交于
create_irq() returns -1 if the interrupt allocation failed, but the code checks for irq == 0. Use create_irq_nr() instead. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Venkatesh Pallipadi <venki@google.com> LKML-Reference: <alpine.LFD.2.00.1009282310360.2416@localhost6.localdomain6> Cc: stable@kernel.org Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Thomas Gleixner 提交于
free_irq_cfg() is not freeing the cpumask_vars in irq_cfg. Fixing this triggers a use after free caused by the fact that copying struct irq_cfg is done with memcpy, which copies the pointer not the cpumask. Fix both places. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yhlu.kernel@gmail.com> LKML-Reference: <alpine.LFD.2.00.1009282052570.2416@localhost6.localdomain6> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Pekka Enberg 提交于
If acpi_evaluate_object() function call doesn't fail, we must kfree() output.buffer before returning from pcc_cpufreq_do_osc(). Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi> Acked-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NDave Jones <davej@redhat.com>
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由 Namhyung Kim 提交于
acpi_perf_data is a percpu pointer but was missing __percpu markup. Add it. Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Acked-by: NTejun Heo <tj@kernel.org> Signed-off-by: NDave Jones <davej@redhat.com>
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- 30 9月, 2010 1 次提交
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由 Cyrill Gorcunov 提交于
Stephane reported we've forgot to guard the P4 platform against spurious in-flight performance IRQs. Fix it. This fixes potential spurious 'dazed and confused' NMI messages. Reported-by: NStephane Eranian <eranian@google.com> Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: NDon Zickus <dzickus@redhat.com> Cc: fweisbec@gmail.com Cc: peterz@infradead.org Cc: Robert Richter <robert.richter@amd.com> Cc: Lin Ming <ming.m.lin@intel.com> LKML-Reference: <1285815698-4298-1-git-send-email-dzickus@redhat.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 29 9月, 2010 2 次提交
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由 Namhyung Kim 提交于
cpu_cstate_entry is a percpu pointer but was missing __percpu markup. Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Acked-by: NTejun Heo <tj@kernel.org> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 H. Peter Anvin 提交于
After uncapping the CPUID level, we need to also re-run the CPU feature detection code. This resolves kernel bugzilla 16322. Reported-by: Nboris64 <bugzilla.kernel.org@boris64.net> Cc: <stable@kernel.org> v2.6.29..2.6.35 LKML-Reference: <tip-@git.kernel.org> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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- 27 9月, 2010 1 次提交
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由 Alexander Chumachenko 提交于
While debugging bit_spin_lock() hang, it was tracked down to gcc-4.4 misoptimization of non-inlined constant_test_bit() due to non-volatile addr when 'const volatile unsigned long *addr' cast to 'unsigned long *' with subsequent unconditional jump to pause (and not to the test) leading to hang. Compiling with gcc-4.3 or disabling CONFIG_OPTIMIZE_INLINING yields inlined constant_test_bit() and correct jump, thus working around the kernel bug. Other arches than asm-x86 may implement this slightly differently; 2.6.29 mitigates the misoptimization by changing the function prototype (commit c4295fbb) but probably fixing the issue itself is better. Signed-off-by: NAlexander Chumachenko <ledest@gmail.com> Signed-off-by: NMichael Shigorin <mike@osdn.org.ua> Acked-by: NLinus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
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- 25 9月, 2010 1 次提交
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由 Jan Beulich 提交于
Using cpuid_eax() to determine feature availability on other than the current CPU is invalid. And feature availability should also be checked in the hotplug code path. Signed-off-by: NJan Beulich <jbeulich@novell.com> Cc: Rudolf Marek <r.marek@assembler.cz> Cc: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: NGuenter Roeck <guenter.roeck@ericsson.com>
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- 24 9月, 2010 1 次提交
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由 Robert Richter 提交于
Some cpus still deliver spurious interrupts after disabling a counter. This caused 'undelivered NMI' messages. This patch fixes this. Introduced by: 4177c42a: perf, x86: Try to handle unknown nmis with an enabled PMU Reported-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NRobert Richter <robert.richter@amd.com> Cc: Don Zickus <dzickus@redhat.com> Cc: gorcunov@gmail.com <gorcunov@gmail.com> Cc: fweisbec@gmail.com <fweisbec@gmail.com> Cc: ying.huang@intel.com <ying.huang@intel.com> Cc: ming.m.lin@intel.com <ming.m.lin@intel.com> Cc: yinghai@kernel.org <yinghai@kernel.org> Cc: andi@firstfloor.org <andi@firstfloor.org> Cc: eranian@google.com <eranian@google.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <20100915162034.GO13563@erda.amd.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 23 9月, 2010 5 次提交
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由 Joerg Roedel 提交于
In the __unmap_single function the dma_addr is rounded down to a page boundary before the dma pages are unmapped. The address is later also used to flush the TLB entries for that mapping. But without the offset into the dma page the amount of pages to flush might be miscalculated in the TLB flushing path. This patch fixes this bug by using the original address to flush the TLB. Cc: stable@kernel.org Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
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由 Joerg Roedel 提交于
This patch adds a workaround for an IOMMU BIOS problem to the AMD IOMMU driver. The result of the bug is that the IOMMU does not execute commands anymore when the system comes out of the S3 state resulting in system failure. The bug in the BIOS is that is does not restore certain hardware specific registers correctly. This workaround reads out the contents of these registers at boot time and restores them on resume from S3. The workaround is limited to the specific IOMMU chipset where this problem occurs. Cc: stable@kernel.org Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
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由 Joerg Roedel 提交于
This patch moves the setting of the configuration and feature flags out out the acpi table parsing path and moves it into the iommu-enable path. This is needed to reliably fix resume-from-s3. Cc: stable@kernel.org Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
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由 Steven Rostedt 提交于
The guest can use the paravirt clock in kvmclock.c which is used by sched_clock(), which in turn is used by the tracing mechanism for timestamps, which leads to infinite recursion. Disable mcount/tracing for kvmclock.o. Cc: stable@kernel.org Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Avi Kivity <avi@redhat.com> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
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由 Jeremy Fitzhardinge 提交于
When using a paravirt clock, pvclock.c can be used by sched_clock(), which in turn is used by the tracing mechanism for timestamps, which leads to infinite recursion. Disable mcount/tracing for pvclock.o. Cc: stable@kernel.org Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> LKML-Reference: <4C9A9A3F.4040201@goop.org> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
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- 22 9月, 2010 2 次提交
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由 Yinghai Lu 提交于
earlyprintk can take and I/O port, so we need to handle this case in the setup code too, otherwise 0x3f8 will be treated as a baud rate. Signed-off-by: NYinghai Lu <yinghai@kernel.org> LKML-Reference: <4C7B05A6.4010801@kernel.org> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Yinghai Lu 提交于
Torsten reported that there is garbage output, after commit 8fee13a4 (x86, setup: enable early console output from the decompressor) It turns out we missed the offset for that case. Reported-by: NTorsten Kaiser <just.for.lkml@googlemail.com> Signed-off-by: NYinghai Lu <yinghai@kernel.org> LKML-Reference: <4C7B0578.8090807@kernel.org> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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- 21 9月, 2010 2 次提交
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由 Jiri Olsa 提交于
This patch adds CPU type detection for dunnington processor (Family 6 / Model 29) to be identified as core 2 family cpu type (wikipedia source). I tested oprofile on Intel(R) Xeon(R) CPU E7440 reporting itself as model 29, and it runs without an issue. Spec: http://www.intel.com/Assets/en_US/PDF/specupdate/320336.pdfSigned-off-by: NJiri Olsa <jolsa@redhat.com> Acked-by: NAndi Kleen <ak@linux.intel.com> Cc: stable@kernel.org Signed-off-by: NRobert Richter <robert.richter@amd.com>
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由 Rusty Russell 提交于
We used to have a hypercall which reloaded the entire GDT, then we switched to one which loaded a single entry (to match the IDT code). Some comments were not updated, so fix them. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Reported by: Eviatar Khen <eviatarkhen@gmail.com>
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- 17 9月, 2010 1 次提交
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由 Frederic Weisbecker 提交于
Lengths and types of breakpoints are encoded in a half byte into CPU registers. However when we extract these values and store them, we add a high half byte part to them: 0x40 to the length and 0x80 to the type. When that gets reloaded to the CPU registers, the high part is masked. While making the instruction breakpoints available for perf, I zapped that high part on instruction breakpoint encoding and that broke the arch -> generic translation used by ptrace instruction breakpoints. Writing dr7 to set an inst breakpoint was then failing. There is no apparent reason for these high parts so we could get rid of them altogether. That's an invasive change though so let's do that later and for now fix the problem by restoring that inst breakpoint high part encoding in this sole patch. Reported-by: NKelvie Wong <kelvie@ieee.org> Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Will Deacon <will.deacon@arm.com>
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- 16 9月, 2010 1 次提交
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由 Patrick Simmons 提交于
This patch adds CPU type detection for the Intel Celeron 540, which is part of the Core 2 family according to Wikipedia; the family and ID pair is absent from the Volume 3B table referenced in the source code comments. I have tested this patch on an Intel Celeron 540 machine reporting itself as Family 6 Model 22, and OProfile runs on the machine without issue. Spec: http://download.intel.com/design/mobile/SPECUPDT/317667.pdfSigned-off-by: NPatrick Simmons <linuxrocks123@netscape.net> Acked-by: NAndi Kleen <ak@linux.intel.com> Acked-by: NArnd Bergmann <arnd@arndb.de> Cc: stable@kernel.org Signed-off-by: NRobert Richter <robert.richter@amd.com>
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- 15 9月, 2010 4 次提交
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由 Roland McGrath 提交于
In commit d4d67150, we reopened an old hole for a 64-bit ptracer touching a 32-bit tracee in system call entry. A %rax value set via ptrace at the entry tracing stop gets used whole as a 32-bit syscall number, while we only check the low 32 bits for validity. Fix it by truncating %rax back to 32 bits after syscall_trace_enter, in addition to testing the full 64 bits as has already been added. Reported-by: NBen Hawkes <hawkes@sota.gen.nz> Signed-off-by: NRoland McGrath <roland@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 H. Peter Anvin 提交于
On 64 bits, we always, by necessity, jump through the system call table via %rax. For 32-bit system calls, in theory the system call number is stored in %eax, and the code was testing %eax for a valid system call number. At one point we loaded the stored value back from the stack to enforce zero-extension, but that was removed in checkin d4d67150. An actual 32-bit process will not be able to introduce a non-zero-extended number, but it can happen via ptrace. Instead of re-introducing the zero-extension, test what we are actually going to use, i.e. %rax. This only adds a handful of REX prefixes to the code. Reported-by: NBen Hawkes <hawkes@sota.gen.nz> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com> Cc: <stable@kernel.org> Cc: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org>
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由 H. Peter Anvin 提交于
compat_alloc_user_space() expects the caller to independently call access_ok() to verify the returned area. A missing call could introduce problems on some architectures. This patch incorporates the access_ok() check into compat_alloc_user_space() and also adds a sanity check on the length. The existing compat_alloc_user_space() implementations are renamed arch_compat_alloc_user_space() and are used as part of the implementation of the new global function. This patch assumes NULL will cause __get_user()/__put_user() to either fail or access userspace on all architectures. This should be followed by checking the return value of compat_access_user_space() for NULL in the callers, at which time the access_ok() in the callers can also be removed. Reported-by: NBen Hawkes <hawkes@sota.gen.nz> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com> Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: NChris Metcalf <cmetcalf@tilera.com> Acked-by: NDavid S. Miller <davem@davemloft.net> Acked-by: NIngo Molnar <mingo@elte.hu> Acked-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NTony Luck <tony.luck@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: James Bottomley <jejb@parisc-linux.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: <stable@kernel.org>
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由 Thomas Gleixner 提交于
This more or less reverts commits 08be9796 (x86: Force HPET readback_cmp for all ATI chipsets) and 30a564be (x86, hpet: Restrict read back to affected ATI chipsets) to the status of commit 8da854cb (x86, hpet: Erratum workaround for read after write of HPET comparator). The delta to commit 8da854cb is mostly comments and the change from WARN_ONCE to printk_once as we know the call path of this function already. This needs really in depth explanation: First of all the HPET design is a complete failure. Having a counter compare register which generates an interrupt on matching values forces the software to do at least one superfluous readback of the counter register. While it is nice in theory to program "absolute" time events it is practically useless because the timer runs at some absurd frequency which can never be matched to real world units. So we are forced to calculate a relative delta and this forces a readout of the actual counter value, adding the delta and programming the compare register. When the delta is small enough we run into the danger that we program a compare value which is already in the past. Due to the compare for equal nature of HPET we need to read back the counter value after writing the compare rehgister (btw. this is necessary for absolute timeouts as well) to make sure that we did not miss the timer event. We try to work around that by setting the minimum delta to a value which is larger than the theoretical time which elapses between the counter readout and the compare register write, but that's only true in theory. A NMI or SMI which hits between the readout and the write can easily push us beyond that limit. This would result in waiting for the next HPET timer interrupt until the 32bit wraparound of the counter happens which takes about 306 seconds. So we designed the next event function to look like: match = read_cnt() + delta; write_compare_ref(match); return read_cnt() < match ? 0 : -ETIME; At some point we got into trouble with certain ATI chipsets. Even the above "safe" procedure failed. The reason was that the write to the compare register was delayed probably for performance reasons. The theory was that they wanted to avoid the synchronization of the write with the HPET clock, which is understandable. So the write does not hit the compare register directly instead it goes to some intermediate register which is copied to the real compare register in sync with the HPET clock. That opens another window for hitting the dreaded "wait for a wraparound" problem. To work around that "optimization" we added a read back of the compare register which either enforced the update of the just written value or just delayed the readout of the counter enough to avoid the issue. We unfortunately never got any affirmative info from ATI/AMD about this. One thing is sure, that we nuked the performance "optimization" that way completely and I'm pretty sure that the result is worse than before some HW folks came up with those. Just for paranoia reasons I added a check whether the read back compare register value was the same as the value we wrote right before. That paranoia check triggered a couple of years after it was added on an Intel ICH9 chipset. Venki added a workaround (commit 8da854cb) which was reading the compare register twice when the first check failed. We considered this to be a penalty in general and restricted the readback (thus the wasted CPU cycles) to the known to be affected ATI chipsets. This turned out to be a utterly wrong decision. 2.6.35 testers experienced massive problems and finally one of them bisected it down to commit 30a564be which spured some further investigation. Finally we got confirmation that the write to the compare register can be delayed by up to two HPET clock cycles which explains the problems nicely. All we can do about this is to go back to Venki's initial workaround in a slightly modified version. Just for the record I need to say, that all of this could have been avoided if hardware designers and of course the HPET committee would have thought about the consequences for a split second. It's out of my comprehension why designing a working timer is so hard. There are two ways to achieve it: 1) Use a counter wrap around aware compare_reg <= counter_reg implementation instead of the easy compare_reg == counter_reg Downsides: - It needs more silicon. - It needs a readout of the counter to apply a relative timeout. This is necessary as the counter does not run in any useful (and adjustable) frequency and there is no guarantee that the counter which is used for timer events is the same which is used for reading the actual time (and therefor for calculating the delta) Upsides: - None 2) Use a simple down counter for relative timer events Downsides: - Absolute timeouts are not possible, which is not a problem at all in the context of an OS and the expected max. latencies/jitter (also see Downsides of #1) Upsides: - It needs less or equal silicon. - It works ALWAYS - It is way faster than a compare register based solution (One write versus one write plus at least one and up to four reads) I would not be so grumpy about all of this, if I would not have been ignored for many years when pointing out these flaws to various hardware folks. I really hate timers (at least those which seem to be designed by janitors). Though finally we got a reasonable explanation plus a solution and I want to thank all the folks involved in chasing it down and providing valuable input to this. Bisected-by: NNix <nix@esperi.org.uk> Reported-by: NArtur Skawina <art.08.09@gmail.com> Reported-by: NDamien Wyart <damien.wyart@free.fr> Reported-by: NJohn Drescher <drescherjm@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: stable@kernel.org Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 14 9月, 2010 2 次提交
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The arch/x86/Makefile uses scripts/gcc-x86_$(BITS)-has-stack-protector.sh to check if cc1 supports -fstack-protector. When -fPIE is passed to cc1, these scripts fail causing stack protection to be disabled even when it is available. This fix is similar to commit c47efe55Reported-by: NKai Dietrich <mail@cleeus.de> Signed-off-by: NMagnus Granberg <zorry@gentoo.org> LKML-Reference: <20100913101319.748A1148E216@opensource.dyc.edu> Signed-off-by: NAnthony G. Basile <basile@opensource.dyc.edu> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Tetsuo Handa 提交于
Gcc 3.x generates a warning arch/x86/include/asm/cpufeature.h: In function `__static_cpu_has': arch/x86/include/asm/cpufeature.h:326: warning: asm operand 1 probably doesn't match constraints on each file. But static_cpu_has() for gcc 3.x does not need __static_cpu_has(). Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> LKML-Reference: <201008300127.o7U1RC6Z044051@www262.sakura.ne.jp> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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- 11 9月, 2010 2 次提交
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由 Peter Zijlstra 提交于
Doh, a real life genuine preemption leak.. This caused a suspend failure. Reported-bisected-and-tested-by-the-invaluable: Jeff Chua <jeff.chua.linux@gmail.com> Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Nico Schottelius <nico-linux-20100709@schottelius.org> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Florian Pritz <flo@xssn.at> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: <stable@kernel.org> # Greg, please apply after: cd7240c0 ("x86, tsc, sched: Recompute cyc2ns_offset's during resume from") sleep states LKML-Reference: <1284150773.402.122.camel@laptop> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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由 Peter Zijlstra 提交于
A real life genuine preemption leak.. Reported-and-tested-by: NJeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 10 9月, 2010 1 次提交
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由 Jack Steiner 提交于
Fix calculation of "max_pnode" for systems where the the highest blade has neither cpus or memory. (And, yes, although rare this does occur). Signed-off-by: NJack Steiner <steiner@sgi.com> LKML-Reference: <20100910150808.GA19802@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 09 9月, 2010 3 次提交
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由 Gleb Natapov 提交于
Top of kvm_kpic_state structure should have the same memory layout as kvm_pic_state since it is copied by memcpy. Signed-off-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Avi Kivity 提交于
If there are no vcpus, found will be NULL. Check before doing anything with it. Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Avi Kivity 提交于
operand::val and operand::orig_val are 32-bit on i386, whereas cmpxchg8b operands are 64-bit. Fix by adding val64 and orig_val64 union members to struct operand, and using them where needed. Signed-off-by: NAvi Kivity <avi@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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