summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/head_64.S
AgeCommit message (Collapse)AuthorFilesLines
2013-05-28x86-64, init: Fix a possible wraparound bug in switchover in head_64.SZhang Yanfei1-2/+4
In head_64.S, a switchover has been used to handle kernel crossing 1G, 512G boundaries. And commit 8170e6bed465b4b0c7687f93e9948aca4358a33b x86, 64bit: Use a #PF handler to materialize early mappings on demand said: During the switchover in head_64.S, before #PF handler is available, we use three pages to handle kernel crossing 1G, 512G boundaries with sharing page by playing games with page aliasing: the same page is mapped twice in the higher-level tables with appropriate wraparound. But from the switchover code, when we set up the PUD table: 114 addq $4096, %rdx 115 movq %rdi, %rax 116 shrq $PUD_SHIFT, %rax 117 andl $(PTRS_PER_PUD-1), %eax 118 movq %rdx, (4096+0)(%rbx,%rax,8) 119 movq %rdx, (4096+8)(%rbx,%rax,8) It seems line 119 has a potential bug there. For example, if the kernel is loaded at physical address 511G+1008M, that is 000000000 111111111 111111000 000000000000000000000 and the kernel _end is 512G+2M, that is 000000001 000000000 000000001 000000000000000000000 So in this example, when using the 2nd page to setup PUD (line 114~119), rax is 511. In line 118, we put rdx which is the address of the PMD page (the 3rd page) into entry 511 of the PUD table. But in line 119, the entry we calculate from (4096+8)(%rbx,%rax,8) has exceeded the PUD page. IMO, the entry in line 119 should be wraparound into entry 0 of the PUD table. The patch fixes the bug. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Link: http://lkml.kernel.org/r/5191DE5A.3020302@cn.fujitsu.com Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: <stable@vger.kernel.org> v3.9 Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-05-02x86-64, init: Do not set NX bits on non-NX capable hardwareH. Peter Anvin1-0/+1
During early init, we would incorrectly set the NX bit even if the NX feature was not supported. Instead, only set this bit if NX is actually available and enabled. We already do very early detection of the NX bit to enable it in EFER, this simply extends this detection to the early page table mask. Reported-by: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1367476850.5660.2.camel@nexus Cc: <stable@vger.kernel.org> v3.9
2013-02-27Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more x86 fixes from Peter Anvin: "Additional x86 fixes. Three of these patches are pure documentation, two are pretty trivial; the remaining one fixes boot problems on some non-BIOS machines." * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Make sure we can boot in the case the BDA contains pure garbage x86, efi: Mark disable_runtime as __initdata x86, doc: Fix incorrect comment about 64-bit code segment descriptors doc, kernel-parameters: Document 'console=hvc<n>' doc, xen: Mention 'earlyprintk=xen' in the documentation. ACPI: Overriding ACPI tables via initrd only works with an initrd and on X86
2013-02-25x86, doc: Fix incorrect comment about 64-bit code segment descriptorsKonrad Rzeszutek Wilk1-2/+2
The AMD64 Architecture Programmer's Manual Volume 2, on page 89 mentions: "If the processor is running in 64-bit mode (L=1), the only valid setting of the D bit is 0." This matches with what the code does. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Link: http://lkml.kernel.org/r/1361825650-14031-4-git-send-email-konrad.wilk@oracle.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-22x86-64: don't set the early IDT to point directly to 'early_idt_handler'Linus Torvalds1-0/+2
The code requires the use of the proper per-exception-vector stub functions (set up as the early_idt_handlers[] array - note the 's') that make sure to set up the error vector number. This is true regardless of whether CONFIG_EARLY_PRINTK is set or not. Why? The stack offset for the comparison of __KERNEL_CS won't be right otherwise, nor will the new check (from commit 8170e6bed465: "x86, 64bit: Use a #PF handler to materialize early mappings on demand") for the page fault exception vector. Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-29x86, 64bit: Use a #PF handler to materialize early mappings on demandH. Peter Anvin1-83/+127
Linear mode (CR0.PG = 0) is mutually exclusive with 64-bit mode; all 64-bit code has to use page tables. This makes it awkward before we have first set up properly all-covering page tables to access objects that are outside the static kernel range. So far we have dealt with that simply by mapping a fixed amount of low memory, but that fails in at least two upcoming use cases: 1. We will support load and run kernel, struct boot_params, ramdisk, command line, etc. above the 4 GiB mark. 2. need to access ramdisk early to get microcode to update that as early possible. We could use early_iomap to access them too, but it will make code to messy and hard to be unified with 32 bit. Hence, set up a #PF table and use a fixed number of buffers to set up page tables on demand. If the buffers fill up then we simply flush them and start over. These buffers are all in __initdata, so it does not increase RAM usage at runtime. Thus, with the help of the #PF handler, we can set the final kernel mapping from blank, and switch to init_level4_pgt later. During the switchover in head_64.S, before #PF handler is available, we use three pages to handle kernel crossing 1G, 512G boundaries with sharing page by playing games with page aliasing: the same page is mapped twice in the higher-level tables with appropriate wraparound. The kernel region itself will be properly mapped; other mappings may be spurious. early_make_pgtable is using kernel high mapping address to access pages to set page table. -v4: Add phys_base offset to make kexec happy, and add init_mapping_kernel() - Yinghai -v5: fix compiling with xen, and add back ident level3 and level2 for xen also move back init_level4_pgt from BSS to DATA again. because we have to clear it anyway. - Yinghai -v6: switch to init_level4_pgt in init_mem_mapping. - Yinghai -v7: remove not needed clear_page for init_level4_page it is with fill 512,8,0 already in head_64.S - Yinghai -v8: we need to keep that handler alive until init_mem_mapping and don't let early_trap_init to trash that early #PF handler. So split early_trap_pf_init out and move it down. - Yinghai -v9: switchover only cover kernel space instead of 1G so could avoid touch possible mem holes. - Yinghai -v11: change far jmp back to far return to initial_code, that is needed to fix failure that is reported by Konrad on AMD systems. - Yinghai Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1359058816-7615-12-git-send-email-yinghai@kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-11-14x86-64, hotplug: Add start_cpu0() entry point to head_64.SFenghua Yu1-0/+16
start_cpu0() is defined in head_64.S for 64-bit. The function sets up stack and jumps to start_secondary() for CPU0 wake up. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1352835171-3958-8-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-29Merge branch 'x86-trampoline-for-linus' of ↵Linus Torvalds1-4/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 trampoline rework from H. Peter Anvin: "This code reworks all the "trampoline"/"realmode" code (various bits that need to live in the first megabyte of memory, most but not all of which runs in real mode at some point) in the kernel into a single object. The main reason for doing this is that it eliminates the last place in the kernel where we needed pages to be mapped RWX. This code separates all that code into proper R/RW/RX pages." Fix up conflicts in arch/x86/kernel/Makefile (mca removed next to reboot code), and arch/x86/kernel/reboot.c (reboot code moved around in one branch, modified in this one), and arch/x86/tools/relocs.c (mostly same code came in earlier due to working around the ld bugs just before the 3.4 release). Also remove stale x86-relocs entry from scripts/.gitignore as per Peter Anvin. * commit '61f5446169046c217a5479517edac3a890c3bee7': (36 commits) x86, realmode: Move end signature into header.S x86, relocs: When printing an error, say relative or absolute x86, relocs: More relocations which may end up as absolute x86, relocs: Workaround for binutils 2.22.52.0.1 section bug xen-acpi-processor: Add missing #include <xen/xen.h> acpi, bgrd: Add missing <linux/io.h> to drivers/acpi/bgrt.c x86, realmode: Change EFER to a single u64 field x86, realmode: Move kernel/realmode.c to realmode/init.c x86, realmode: Move not-common bits out of trampoline_common.S x86, realmode: Mask out EFER.LMA when saving trampoline EFER x86, realmode: Fix no cache bits test in reboot_32.S x86, realmode: Make sure all generated files are listed in targets x86, realmode: build fix: remove duplicate build x86, realmode: read cr4 and EFER from kernel for 64-bit trampoline x86, realmode: fixes compilation issue in tboot.c x86, realmode: move relocs from scripts/ to arch/x86/tools x86, realmode: header for trampoline code x86, realmode: flattened rm hierachy x86, realmode: don't copy real_mode_header x86, realmode: fix 64-bit wakeup sequence ...
2012-05-08x86, realmode: Move SMP trampoline to unified realmode codeJarkko Sakkinen1-4/+0
Migrated SMP trampoline code to the real mode blob. SMP trampoline code is not yet removed from .x86_trampoline because it is needed by the wakeup code. [ hpa: always enable compiling startup_32_smp in head_32.S... it is only a few instructions which go into .init on UP builds, and it makes the rest of the code less #ifdef ugly. ] Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-6-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-04-19x86-64: Handle exception table entries during early bootH. Peter Anvin1-19/+57
If we get an exception during early boot, walk the exception table to see if we should intercept it. The main use case for this is to allow rdmsr_safe()/wrmsr_safe() during CPU initialization. Since the exception table is currently sorted at runtime, and fairly late in startup, this code walks the exception table linearly. We obviously don't need to worry about modules, however: none have been loaded at this point. [ v2: Use early_fixup_exception() instead of linear search ] Link: http://lkml.kernel.org/r/1334794610-5546-5-git-send-email-hpa@zytor.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-04-19x86, paravirt: Replace GET_CR2_INTO_RCX with GET_CR2_INTO_RAXH. Peter Anvin1-3/+3
GET_CR2_INTO_RCX is asinine: it is only used in one place, the actual paravirt call returns the value in %rax, not %rcx; and the one place that wants it wants the result in %r9. We actually generate as a result of this call: call ... movq %rax, %rcx xorq %rax, %rax /* this value isn't even used... */ movq %rcx, %r9 At least make the macro do what the paravirt call does, which is put the value into %rax. Nevermind the fact that the macro clobbers all the volatile registers. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1334794610-5546-4-git-send-email-hpa@zytor.com Cc: Glauber de Oliveira Costa <glommer@parallels.com>
2012-04-19x86: Add symbolic constant for exceptions with error codeH. Peter Anvin1-1/+1
Add a symbolic constant for the bitmask which states which exceptions carry an error code. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1334794610-5546-3-git-send-email-hpa@zytor.com
2011-12-21x86: Keep current stack in NMI breakpointsSteven Rostedt1-0/+4
We want to allow NMI handlers to have breakpoints to be able to remove stop_machine from ftrace, kprobes and jump_labels. But if an NMI interrupts a current breakpoint, and then it triggers a breakpoint itself, it will switch to the breakpoint stack and corrupt the data on it for the breakpoint processing that it interrupted. Instead, have the NMI check if it interrupted breakpoint processing by checking if the stack that is currently used is a breakpoint stack. If it is, then load a special IDT that changes the IST for the debug exception to keep the same stack in kernel context. When the NMI is done, it puts it back. This way, if the NMI does trigger a breakpoint, it will keep using the same stack and not stomp on the breakpoint data for the breakpoint it interrupted. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-17x86, trampoline: Common infrastructure for low memory trampolinesH. Peter Anvin1-2/+1
Common infrastructure for low memory trampolines. This code installs the trampolines permanently in low memory very early. It also permits multiple pieces of code to be used for this purpose. This code also introduces a standard infrastructure for computing symbol addresses in the trampoline code. The only change to the actual SMP trampolines themselves is that the 64-bit trampoline has been made reusable -- the previous version would overwrite the code with a status variable; this moves the status variable to a separate location. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <4D5DFBE4.7090104@intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Matthieu Castet <castet.matthieu@free.fr> Cc: Stephen Rothwell <sfr@canb.auug.org.au>
2010-07-21x86-64: Simplify loading initial_gsBrian Gerst1-3/+2
Load initial_gs as two 32-bit values instead of splitting a 64-bit value. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1279371808-24804-3-git-send-email-brgerst@gmail.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-09tree-wide: Assorted spelling fixesDaniel Mack1-1/+1
In particular, several occurances of funny versions of 'success', 'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address', 'beginning', 'desirable', 'separate' and 'necessary' are fixed. Signed-off-by: Daniel Mack <daniel@caiaq.de> Cc: Joe Perches <joe@perches.com> Cc: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-08Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (36 commits) x86, mm: Correct the implementation of is_untracked_pat_range() x86/pat: Trivial: don't create debugfs for memtype if pat is disabled x86, mtrr: Fix sorting of mtrr after subtracting x86: Move find_smp_config() earlier and avoid bootmem usage x86, platform: Change is_untracked_pat_range() to bool; cleanup init x86: Change is_ISA_range() into an inline function x86, mm: is_untracked_pat_range() takes a normal semiclosed range x86, mm: Call is_untracked_pat_range() rather than is_ISA_range() x86: UV SGI: Don't track GRU space in PAT x86: SGI UV: Fix BAU initialization x86, numa: Use near(er) online node instead of roundrobin for NUMA x86, numa, bootmem: Only free bootmem on NUMA failure path x86: Change crash kernel to reserve via reserve_early() x86: Eliminate redundant/contradicting cache line size config options x86: When cleaning MTRRs, do not fold WP into UC x86: remove "extern" from function prototypes in <asm/proto.h> x86, mm: Report state of NX protections during boot x86, mm: Clean up and simplify NX enablement x86, pageattr: Make set_memory_(x|nx) aware of NX support x86, sleep: Always save the value of EFER ... Fix up conflicts (added both iommu_shutdown and is_untracked_pat_range) to 'struct x86_platform_ops') in arch/x86/include/asm/x86_init.h arch/x86/kernel/x86_init.c
2009-12-05Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: include/linux/compiler-gcc4.h: Fix build bug - gcc-4.0.2 doesn't understand __builtin_object_size x86/alternatives: No need for alternatives-asm.h to re-invent stuff already in asm.h x86/alternatives: Check replacementlen <= instrlen at build time x86, 64-bit: Set data segments to null after switching to 64-bit mode x86: Clean up the loadsegment() macro x86: Optimize loadsegment() x86: Add missing might_fault() checks to copy_{to,from}_user() x86-64: __copy_from_user_inatomic() adjustments x86: Remove unused thread_return label from switch_to() x86, 64-bit: Fix bstep_iret jump x86: Don't use the strict copy checks when branch profiling is in use x86, 64-bit: Move K8 B step iret fixup to fault entry asm x86: Generate cmpxchg build failures x86: Add a Kconfig option to turn the copy_from_user warnings into errors x86: Turn the copy_from_user check into an (optional) compile time warning x86: Use __builtin_memset and __builtin_memcpy for memset/memcpy x86: Use __builtin_object_size() to validate the buffer size for copy_from_user()
2009-11-26x86, 64-bit: Set data segments to null after switching to 64-bit modeBrian Gerst1-2/+2
This prevents kernel threads from inheriting non-null segment selectors, and causing optimizations in __switch_to() to be ineffective. Signed-off-by: Brian Gerst <brgerst@gmail.com> Cc: Tim Blechmann <tim@klingt.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jan Beulich <JBeulich@novell.com> LKML-Reference: <1259165856-3512-1-git-send-email-brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-20x86-64: preserve large page mapping for 1st 2MB kernel txt with ↵Suresh Siddha1-1/+2
CONFIG_DEBUG_RODATA In the first 2MB, kernel text is co-located with kernel static page tables setup by head_64.S. CONFIG_DEBUG_RODATA chops this 2MB large page mapping to small 4KB pages as we mark the kernel text as RO, leaving the static page tables as RW. With CONFIG_DEBUG_RODATA disabled, OLTP run on NHM-EP shows 1% improvement with 2% reduction in system time and 1% improvement in iowait idle time. To recover this, move the kernel static page tables to .data section, so that we don't have to break the first 2MB of kernel text to small pages with CONFIG_DEBUG_RODATA. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <20091014220254.063193621@sbs-t61.sc.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-26Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Remove redundant non-NUMA topology functions x86: early_printk: Protect against using the same device twice x86: Reduce verbosity of "PAT enabled" kernel message x86: Reduce verbosity of "TSC is reliable" message x86: mce: Use safer ways to access MCE registers x86: mce, inject: Use real inject-msg in raise_local x86: mce: Fix thermal throttling message storm x86: mce: Clean up thermal throttling state tracking code x86: split NX setup into separate file to limit unstack-protected code xen: check EFER for NX before setting up GDT mapping x86: Cleanup linker script using new linker script macros. x86: Use section .data.page_aligned for the idt_table. x86: convert to use __HEAD and HEAD_TEXT macros. x86: convert compressed loader to use __HEAD and HEAD_TEXT macros. x86: fix fragile computation of vsyscall address
2009-09-21Use macros for .bss.page_aligned section.Tim Abbott1-1/+1
This patch changes the remaining direct references to .bss.page_aligned in C and assembly code to use the macros in include/linux/linkage.h. Signed-off-by: Tim Abbott <tabbott@ksplice.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-18x86: convert to use __HEAD and HEAD_TEXT macros.Tim Abbott1-1/+1
This has the consequence of changing the section name use for head code from ".text.head" to ".head.text". It also eliminates the ".text.head" output section (instead placing head code at the start of the .text output section), which should be harmless. This patch only changes the sections in the actual kernel, not those in the compressed boot loader. Signed-off-by: Tim Abbott <tabbott@ksplice.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-06-17x86: de-assembler-ize asm/desc.hAlexander van Heukelum1-1/+0
asm/desc.h is included in three assembly files, but the only macro it defines, GET_DESC_BASE, is never used. This patch removes the includes, removes the macro GET_DESC_BASE and the ASSEMBLY guard from asm/desc.h. Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24x86: head_64.S - use IDT_ENTRIES instead of hardcoded numberCyrill Gorcunov1-1/+1
Impact: cleanup Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: heukelum@fastmail.fm Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-24x86: head_64.S - remove useless balignCyrill Gorcunov1-2/+0
Impact: cleanup NEXT_PAGE already has 'balign' so no need to keep this redundant one. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: heukelum@fastmail.fm Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-09x86: use linker to offset symbols by __per_cpu_loadBrian Gerst1-19/+2
Impact: cleanup and bug fix Use the linker to create symbols for certain per-cpu variables that are offset by __per_cpu_load. This allows the removal of the runtime fixup of the GDT pointer, which fixes a bug with resume reported by Jiri Slaby. Reported-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Brian Gerst <brgerst@gmail.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20x86: move stack_canary into irq_stackBrian Gerst1-8/+5
Impact: x86_64 percpu area layout change, irq_stack now at the beginning Now that the PDA is empty except for the stack canary, it can be removed. The irqstack is moved to the start of the per-cpu section. If the stack protector is enabled, the canary overlaps the bottom 48 bytes of the irqstack. tj: * updated subject * dropped asm relocation of irq_stack_ptr * updated comments a bit * rebased on top of stack canary changes Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-20x86: rework __per_cpu_load adjustmentsBrian Gerst1-16/+8
Impact: cleanup Use cpu_number to determine if the adjustment is necessary. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-16x86: make pda a percpu variableTejun Heo1-2/+3
[ Based on original patch from Christoph Lameter and Mike Travis. ] As pda is now allocated in percpu area, it can easily be made a proper percpu variable. Make it so by defining per cpu symbol from linker script and declaring it in C code for SMP and simply defining it for UP. This change cleans up code and brings SMP and UP closer a bit. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-16x86: fold pda into percpu area on SMPTejun Heo1-4/+11
[ Based on original patch from Christoph Lameter and Mike Travis. ] Currently pdas and percpu areas are allocated separately. %gs points to local pda and percpu area can be reached using pda->data_offset. This patch folds pda into percpu area. Due to strange gcc requirement, pda needs to be at the beginning of the percpu area so that pda->stack_canary is at %gs:40. To achieve this, a new percpu output section macro - PERCPU_VADDR_PREALLOC() - is added and used to reserve pda sized chunk at the start of the percpu area. After this change, for boot cpu, %gs first points to pda in the data.init area and later during setup_per_cpu_areas() gets updated to point to the actual pda. This means that setup_per_cpu_areas() need to reload %gs for CPU0 while clearing pda area for other cpus as cpu0 already has modified it when control reaches setup_per_cpu_areas(). This patch also removes now unnecessary get_local_pda() and its call sites. A lot of this patch is taken from Mike Travis' "x86_64: Fold pda into per cpu area" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-16x86: load pointer to pda into %gs while brining up a CPUTejun Heo1-5/+10
[ Based on original patch from Christoph Lameter and Mike Travis. ] CPU startup code in head_64.S loaded address of a zero page into %gs for temporary use till pda is loaded but address to the actual pda is available at the point. Load the real address directly instead. This will help unifying percpu and pda handling later on. This patch is mostly taken from Mike Travis' "x86_64: Fold pda into per cpu area" patch. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-16x86: make percpu symbols zerobased on SMPTejun Heo1-1/+23
[ Based on original patch from Christoph Lameter and Mike Travis. ] This patch makes percpu symbols zerobased on x86_64 SMP by adding PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on the percpu output section and using it in vmlinux_64.lds.S. A new PHDR is added as existing ones cannot contain sections near address zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which always points to the vaddr of the loaded percpu data.init region. The following adjustments have been made to accomodate the address change. * code to locate percpu gdt_page in head_64.S is updated to add the load address to the gdt_page offset. * __per_cpu_load is used in places where access to the init data area is necessary. * pda->data_offset is initialized soon after C code is entered as zero value doesn't work anymore. This patch is mostly taken from Mike Travis' "x86_64: Base percpu variables at zero" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-04x86: fix RIP printout in early_idt_handlerJiri Slaby1-1/+1
Impact: fix debug/crash printout Since errorcode is popped out, RIP is on the top of the stack. Use real RIP value instead of wrong CS. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10x86, cpa: rename PTE attribute macros for kernel direct mapping in early bootSuresh Siddha1-2/+2
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: arjan@linux.intel.com Cc: venkatesh.pallipadi@intel.com Cc: jeremy@goop.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16Revert "x86_64: there's no need to preallocate level1_fixmap_pgt"Ingo Molnar1-0/+6
This reverts commit 033786969d1d1b5af12a32a19d3a760314d05329. Suresh Siddha reported that this broke booting on his 2GB testbox. Reported-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16xen64: add xen-head code to head_64.SJeremy Fitzhardinge1-0/+1
Add the Xen entrypoint and ELF notes to head_64.S. Adapts xen-head.S to compile either 32-bit or 64-bit. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16x86_64: there's no need to preallocate level1_fixmap_pgtJeremy Fitzhardinge1-6/+0
Early fixmap will allocate its own L1 pagetable page for fixmap mappings, so there's no need to preallocate one. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08x86: always set _PAGE_GLOBAL in _PAGE_KERNEL* flagsJeremy Fitzhardinge1-2/+2
Consistently set _PAGE_GLOBAL in _PAGE_KERNEL flags. This makes 32- and 64-bit code consistent, and removes some special cases where __PAGE_KERNEL* did not have _PAGE_GLOBAL set, causing confusion as a result of the inconsistencies. This patch only affects x86-64, which generally always supports PGD. The x86-32 patch is next. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08x86: fix CPA self-test for "x86/paravirt: groundwork for 64-bit Xen support"Jeremy Fitzhardinge1-1/+1
Ingo Molnar wrote: > -tip auto-testing found pagetable corruption (CPA self-test failure): > > [ 32.956015] CPA self-test: > [ 32.958822] 4k 2048 large 508 gb 0 x 2556[ffff880000000000-ffff88003fe00000] miss 0 > [ 32.964000] CPA ffff88001d54e000: bad pte 1d4000e3 > [ 32.968000] CPA ffff88001d54e000: unexpected level 2 > [ 32.972000] CPA ffff880022c5d000: bad pte 22c000e3 > [ 32.976000] CPA ffff880022c5d000: unexpected level 2 > [ 32.980000] CPA ffff8800200ce000: bad pte 200000e3 > [ 32.984000] CPA ffff8800200ce000: unexpected level 2 > [ 32.988000] CPA ffff8800210f0000: bad pte 210000e3 > > config and full log can be found at: > > http://redhat.com/~mingo/misc/config-Mon_Jun_30_11_11_51_CEST_2008.bad > http://redhat.com/~mingo/misc/log-Mon_Jun_30_11_11_51_CEST_2008.bad Phew. OK, I've worked this out. Short version is that's it's a false alarm, and there was no real failure here. Long version: * I changed the code to create the physical mapping pagetables to reuse any existing mapping rather than replace it. Specifically, reusing an pud pointed to by the pgd caused this symptom to appear. * The specific PUD being reused is the one created statically in head_64.S, which creates an initial 1GB mapping. * That mapping doesn't have _PAGE_GLOBAL set on it, due to the inconsistency between __PAGE_* and PAGE_*. * The CPA test attempts to clear _PAGE_GLOBAL, and then checks to see that the resulting range is 1) shattered into 4k pages, and 2) has no _PAGE_GLOBAL. * However, since it didn't have _PAGE_GLOBAL on that range to start with, change_page_attr_clear() had nothing to do, and didn't bother shattering the range, * resulting in the reported messages The simple fix is to set _PAGE_GLOBAL in level2_ident_pgt. An additional fix to make CPA testing more robust by using some other pagetable bit (one of the unused available-to-software ones). This would solve spurious CPA test warnings under Xen which uses _PAGE_GLOBAL for its own purposes (ie, not under guest control). Also, we should revisit the use of _PAGE_GLOBAL in asm-x86/pgtable.h, and use it consistently, and drop MAKE_GLOBAL. The first time I proposed it it caused breakages in the very early CPA code; with luck that's all fixed now. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Mark McLoughlin <markmc@redhat.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08paravirt/x86, 64-bit: move __PAGE_OFFSET to leave a space for hypervisorEduardo Habkost1-5/+12
Set __PAGE_OFFSET to the most negative possible address + 16*PGDIR_SIZE. The gap is to allow a space for a hypervisor to fit. The gap is more or less arbitrary, but it's what Xen needs. When booting native, kernel/head_64.S has a set of compile-time generated pagetables used at boot time. This patch removes their absolutely hard-coded layout, and makes it parameterised on __PAGE_OFFSET (and __START_KERNEL_map). Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08x86: move x86_64 gdt closer to i386Glauber Costa1-43/+5
i386 and x86_64 used two different schemes for maintaining the gdt. With this patch, x86_64 initial gdt table is defined in a .c file, same way as i386 is now. Also, we call it "gdt_page", and the descriptor, "early_gdt_descr". This way we achieve common naming, which can allow for more code integration. Signed-off-by: Glauber Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08x86: use stack_start in x86_64Glauber Costa1-2/+3
call x86_64's init_rsp stack_start, just as i386 does. Put a zeroed stack segment for consistency. With this, we can eliminate one ugly ifdef in smpboot.c. Signed-off-by: Glauber Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08Merge branches 'x86/numa-fixes', 'x86/apic', 'x86/apm', 'x86/bitops', ↵Ingo Molnar1-17/+12
'x86/build', 'x86/cleanups', 'x86/cpa', 'x86/cpu', 'x86/defconfig', 'x86/gart', 'x86/i8259', 'x86/intel', 'x86/irqstats', 'x86/kconfig', 'x86/ldt', 'x86/mce', 'x86/memtest', 'x86/pat', 'x86/ptemask', 'x86/resumetrace', 'x86/threadinfo', 'x86/timers', 'x86/vdso' and 'x86/xen' into x86/devel
2008-07-05x86 ACPI: fix resume from suspend to RAM on uniprocessor x86-64Rafael J. Wysocki1-1/+1
Since the trampoline code is now used for ACPI resume from suspend to RAM, the trampoline page tables have to be fixed up during boot not only on SMP systems, but also on UP systems that use the trampoline. Reference: http://bugzilla.kernel.org/show_bug.cgi?id=10923 Reported-by: Dionisus Torimens <djtm@gmx.net> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Andi Kleen <andi@firstfloor.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: pm list <linux-pm@lists.linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25x86: head_64.S cleanup - use PMD_SHIFT instead of numeric constantCyrill Gorcunov1-5/+5
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25x86: head_64.S cleanup - use straight move to CR4 registerCyrill Gorcunov1-3/+1
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25x86: head_64.S cleanup - use predefined flags from processor-flags.hCyrill Gorcunov1-8/+5
We should better use already defined flags from processor-flags.h instead of defining own ones [>>> object code check >>>] original md5sum: 9cfa6dbf045a046bb5dfb85f8bcfe8c4 arch/x86/kernel/head_64.o text data bss dec hex filename 37361 4432 8192 49985 c341 arch/x86/kernel/head_64.o patched md5sum: 9cfa6dbf045a046bb5dfb85f8bcfe8c4 arch/x86/kernel/head_64.o text data bss dec hex filename 37361 4432 8192 49985 c341 arch/x86/kernel/head_64.o [<<< object code check <<<] Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17x86: move suspend wakeup code to CPavel Machek1-4/+0
Move wakeup code to .c, so that video mode setting code can be shared between boot and wakeup. Remove nasty assembly code in 64-bit case by re-using trampoline code. Stack setup was fixed to clear high 16bits of %esp, maybe that fixes some machines. .c code sharing and morse code was done H. Peter Anvin, Sam Ravnborg reviewed kbuild related stuff, and it seems okay to him. Rafael did some cleanups. [rjw: * Made the patch stop breaking compilation on x86-32 * Added arch/x86/kernel/acpi/sleep.h * Got rid of compiler warnings in arch/x86/kernel/acpi/sleep.c * Fixed 32-bit compilation on x86-64 systems * Added include/asm-x86/trampoline.h and fixed the non-SMP compilation on 64-bit x86 * Removed arch/x86/kernel/acpi/sleep_32.c which was not used * Fixed some breakage caused by the integration of smpboot.c done under us in the meantime] Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17x86: move early exception handlers into init.textAndi Kleen1-0/+2
Currently they are in .text.head because the rest of head_64.S. .text.head is not removed as init data, but the early exception handlers should be because they are not needed after early boot of the BP. So move them over. Signed-off-by: Andi Kleen <ak@suse.de> Cc: mingo@elte.hu Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>