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2016-01-20UBSAN: run-time undefined behavior sanity checkerAndrey Ryabinin1-0/+1
UBSAN uses compile-time instrumentation to catch undefined behavior (UB). Compiler inserts code that perform certain kinds of checks before operations that could cause UB. If check fails (i.e. UB detected) __ubsan_handle_* function called to print error message. So the most of the work is done by compiler. This patch just implements ubsan handlers printing errors. GCC has this capability since 4.9.x [1] (see -fsanitize=undefined option and its suboptions). However GCC 5.x has more checkers implemented [2]. Article [3] has a bit more details about UBSAN in the GCC. [1] - https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Debugging-Options.html [2] - https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html [3] - http://developerblog.redhat.com/2014/10/16/gcc-undefined-behavior-sanitizer-ubsan/ Issues which UBSAN has found thus far are: Found bugs: * out-of-bounds access - 97840cb67ff5 ("netfilter: nfnetlink: fix insufficient validation in nfnetlink_bind") undefined shifts: * d48458d4a768 ("jbd2: use a better hash function for the revoke table") * 10632008b9e1 ("clockevents: Prevent shift out of bounds") * 'x << -1' shift in ext4 - http://lkml.kernel.org/r/<5444EF21.8020501@samsung.com> * undefined rol32(0) - http://lkml.kernel.org/r/<1449198241-20654-1-git-send-email-sasha.levin@oracle.com> * undefined dirty_ratelimit calculation - http://lkml.kernel.org/r/<566594E2.3050306@odin.com> * undefined roundown_pow_of_two(0) - http://lkml.kernel.org/r/<1449156616-11474-1-git-send-email-sasha.levin@oracle.com> * [WONTFIX] undefined shift in __bpf_prog_run - http://lkml.kernel.org/r/<CACT4Y+ZxoR3UjLgcNdUm4fECLMx2VdtfrENMtRRCdgHB2n0bJA@mail.gmail.com> WONTFIX here because it should be fixed in bpf program, not in kernel. signed overflows: * 32a8df4e0b33f ("sched: Fix odd values in effective_load() calculations") * mul overflow in ntp - http://lkml.kernel.org/r/<1449175608-1146-1-git-send-email-sasha.levin@oracle.com> * incorrect conversion into rtc_time in rtc_time64_to_tm() - http://lkml.kernel.org/r/<1449187944-11730-1-git-send-email-sasha.levin@oracle.com> * unvalidated timespec in io_getevents() - http://lkml.kernel.org/r/<CACT4Y+bBxVYLQ6LtOKrKtnLthqLHcw-BMp3aqP3mjdAvr9FULQ@mail.gmail.com> * [NOTABUG] signed overflow in ktime_add_safe() - http://lkml.kernel.org/r/<CACT4Y+aJ4muRnWxsUe1CMnA6P8nooO33kwG-c8YZg=0Xc8rJqw@mail.gmail.com> [akpm@linux-foundation.org: fix unused local warning] [akpm@linux-foundation.org: fix __int128 build woes] Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Marek <mmarek@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yury Gribov <y.gribov@samsung.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-16Merge branch 'perf-core-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 perf updates from Ingo Molnar: "This series tightens up RDPMC permissions: currently even highly sandboxed x86 execution environments (such as seccomp) have permission to execute RDPMC, which may leak various perf events / PMU state such as timing information and other CPU execution details. This 'all is allowed' RDPMC mode is still preserved as the (non-default) /sys/devices/cpu/rdpmc=2 setting. The new default is that RDPMC access is only allowed if a perf event is mmap-ed (which is needed to correctly interpret RDPMC counter values in any case). As a side effect of these changes CR4 handling is cleaned up in the x86 code and a shadow copy of the CR4 value is added. The extra CR4 manipulation adds ~ <50ns to the context switch cost between rdpmc-capable and rdpmc-non-capable mms" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Add /sys/devices/cpu/rdpmc=2 to allow rdpmc for all tasks perf/x86: Only allow rdpmc if a perf_event is mapped perf: Pass the event to arch_perf_update_userpage() perf: Add pmu callbacks to track event mapping and unmapping x86: Add a comment clarifying LDT context switching x86: Store a per-cpu shadow copy of CR4 x86: Clean up cr4 manipulation
2015-02-13x86_64: add KASan supportAndrey Ryabinin2-1/+2
This patch adds arch specific code for kernel address sanitizer. 16TB of virtual addressed used for shadow memory. It's located in range [ffffec0000000000 - fffffc0000000000] between vmemmap and %esp fixup stacks. At early stage we map whole shadow region with zero page. Latter, after pages mapped to direct mapping address range we unmap zero pages from corresponding shadow (see kasan_map_shadow()) and allocate and map a real shadow memory reusing vmemmap_populate() function. Also replace __pa with __pa_nodebug before shadow initialized. __pa with CONFIG_DEBUG_VIRTUAL=y make external function call (__phys_addr) __phys_addr is instrumented, so __asan_load could be called before shadow area initialized. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrey Konovalov <adech.fo@gmail.com> Cc: Yuri Gribov <tetra2005@gmail.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Christoph Lameter <cl@linux.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Jim Davis <jim.epost@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-04x86: Store a per-cpu shadow copy of CR4Andy Lutomirski1-1/+1
Context switches and TLB flushes can change individual bits of CR4. CR4 reads take several cycles, so store a shadow copy of CR4 in a per-cpu variable. To avoid wasting a cache line, I added the CR4 shadow to cpu_tlbstate, which is already touched in switch_mm. The heaviest users of the cr4 shadow will be switch_mm and __switch_to_xtra, and __switch_to_xtra is called shortly after switch_mm during context switch, so the cacheline is likely to be hot. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Kees Cook <keescook@chromium.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Vince Weaver <vince@deater.net> Cc: "hillf.zj" <hillf.zj@alibaba-inc.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-16x86/build: Supress realmode.bin is up to date messagePeter Foley1-1/+2
Supress this unnecessary message during kernel re-build: make[3]: 'arch/x86/realmode/rm/realmode.bin' is up to date. Signed-off-by: Peter Foley <pefoley2@pefoley.com> Link: http://lkml.kernel.org/r/1397584693-15902-1-git-send-email-pefoley2@pefoley.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-29Merge commit 'f4bcd8ccddb02833340652e9f46f5127828eb79d' into x86/buildH. Peter Anvin4-17/+12
Bring in upstream merge of x86/kaslr for future patches. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-22x86: Remove duplication of 16-bit CFLAGSDavid Woodhouse1-15/+2
Define them once in arch/x86/Makefile instead of twice. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Link: http://lkml.kernel.org/r/1389180083-23249-1-git-send-email-David.Woodhouse@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-20Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds4-17/+12
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cpu, amd: Fix a shadowed variable situation um, x86: Fix vDSO build x86: Delete non-required instances of include <linux/init.h> x86, realmode: Pointer walk cleanups, pull out invariant use of __pa() x86/traps: Clean up error exception handler definitions
2014-01-06x86: Delete non-required instances of include <linux/init.h>Paul Gortmaker3-3/+0
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. [ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2013-12-18x86, realmode: Pointer walk cleanups, pull out invariant use of __pa()H. Peter Anvin1-14/+12
The pointer arithmetic in this function was really bizarre, where in fact all we really wanted was a simple pointer array walk. Use the much more idiomatic construction for that (*ptr++). Factor an invariant use of __pa() out of the relocation loop. At least on 64 bits it seems gcc isn't capable of doing that automatically. Change the scope of a couple of variables to make it extra obvious that they are extremely local temp variables. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/n/tip-rd908t9c8kvcojdabtmm94mb@git.kernel.org
2013-12-09x86, build: Pass in additional -mno-mmx, -mno-sse optionsH. Peter Anvin1-1/+2
In checkin 5551a34e5aea x86-64, build: Always pass in -mno-sse we unconditionally added -mno-sse to the main build, to keep newer compilers from generating SSE instructions from autovectorization. However, this did not extend to the special environments (arch/x86/boot, arch/x86/boot/compressed, and arch/x86/realmode/rm). Add -mno-sse to the compiler command line for these environments, and add -mno-mmx to all the environments as well, as we don't want a compiler to generate MMX code either. This patch also removes a $(cc-option) call for -m32, since we have long since stopped supporting compilers too old for the -m32 option, and in fact hardcode it in other places in the Makefiles. Reported-by: Kevin B. Smith <kevin.b.smith@intel.com> Cc: Sunil K. Pandey <sunil.k.pandey@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: H. J. Lu <hjl.tools@gmail.com> Link: http://lkml.kernel.org/n/tip-j21wzqv790q834n7yc6g80j1@git.kernel.org Cc: <stable@vger.kernel.org> # build fix only
2013-02-01Merge remote-tracking branch 'origin/x86/mm' into x86/mm2H. Peter Anvin1-2/+2
Explicitly merging these two branches due to nontrivial conflicts and to allow further work. Resolved Conflicts: arch/x86/kernel/head32.c arch/x86/kernel/head64.c arch/x86/mm/init_64.c arch/x86/realmode/init.c Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-29x86, realmode: Separate real_mode reserve and setupYinghai Lu1-12/+20
After we switch to use #PF handler help to set page table, init_level4_pgt will only have entries set after init_mem_mapping(). We need to move copying init_level4_pgt to trampoline_pgd after that. So split reserve and setup, and move the setup after init_mem_mapping() Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1359058816-7615-11-git-send-email-yinghai@kernel.org Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Acked-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-29x86, 64bit, realmode: Use init_level4_pgt to set trampoline_pgd directlyYinghai Lu1-2/+2
with #PF handler way to set early page table, level3_ident will go away with 64bit native path. So just use entries in init_level4_pgt to set them in trampoline_pgd. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1359058816-7615-10-git-send-email-yinghai@kernel.org Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Acked-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-29x86, realmode: Set real_mode permissions earlyYinghai Lu1-5/+6
Trampoline code is executed by APs with kernel low mapping on 64bit. We need to set trampoline code to EXEC early before we boot APs. Found the problem after switching to #PF handler set page table, and we do not set initial kernel low mapping with EXEC anymore in arch/x86/kernel/head_64.S. Change to use early_initcall instead that will make sure trampoline will have EXEC set. -v2: Merge two comments according to Borislav Petkov <bp@alien8.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1359058816-7615-7-git-send-email-yinghai@kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-11-16x86: Use __pa_symbol instead of __pa on C visible symbolsAlexander Duyck1-4/+4
When I made an attempt at separating __pa_symbol and __pa I found that there were a number of cases where __pa was used on an obvious symbol. I also caught one non-obvious case as _brk_start and _brk_end are based on the address of __brk_base which is a C visible symbol. In mark_rodata_ro I was able to reduce the overhead of kernel symbol to virtual memory translation by using a combination of __va(__pa_symbol()) instead of page_address(virt_to_page()). Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-10-02x86, suspend: Correct the restore of CR4, EFER; skip computing EFLAGS.IDH. Peter Anvin1-12/+3
The patch: 73201dbe x86, suspend: On wakeup always initialize cr4 and EFER ... was incorrectly committed in an intermediate (unfinished) form. - We need to test CF, not ZF, for a bit test with btl. - We don't actually need to compute the existence of EFLAGS.ID, since we set a flag at suspend time if CR4 should be restored. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Link: http://lkml.kernel.org/r/1348529239-17943-1-git-send-email-hpa@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-09-26x86, suspend: On wakeup always initialize cr4 and EFERH. Peter Anvin2-10/+21
We already have a flag word to indicate the existence of MISC_ENABLES, so use the same flag word to indicate existence of cr4 and EFER, and always restore them if they exist. That way if something passes a nonzero value when the value *should* be zero, we will still initialize it. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Link: http://lkml.kernel.org/r/1348529239-17943-1-git-send-email-hpa@linux.intel.com
2012-08-10x86, build: Globally set -fno-picAndrew Boie1-1/+1
GCC built with nonstandard options can enable -fpic by default. We never want this for 32-bit kernels and it will break the build. [ hpa: Notably the Android toolchain apparently does this. ] Change-Id: Iaab7d66e598b1c65ac4a4f0229eca2cd3d0d2898 Signed-off-by: Andrew Boie <andrew.p.boie@intel.com> Link: http://lkml.kernel.org/r/1344624546-29691-1-git-send-email-andrew.p.boie@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-06-21x86-64, reboot: Be more paranoid in 64-bit reboot=biosH. Peter Anvin1-2/+6
Be a bit more paranoid in the transition back to 16-bit mode. In particular, in case the kernel is residing above the 4 GiB mark, switch to the trampoline GDT, and make the jump after turning off paging a far jump. In theory, none of this should matter, but it is exactly the kind of things that broken SMM or virtualization software could trip up on. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/tip-jopx7y6g6dbcx4tpal8q0jlr@git.kernel.org
2012-06-17x86-64, reboot: Allow reboot=bios and reboot-cpu override on x86-64H. Peter Anvin3-5/+27
With the revamped realmode trampoline code, it is trivial to extend support for reboot=bios to x86-64. Furthermore, while we are at it, remove the restriction that only we can only override the reboot CPU on 32 bits. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/n/tip-jopx7y6g6dbcx4tpal8q0jlr@git.kernel.org
2012-05-21x86, realmode: Move end signature into header.SH. Peter Anvin4-6/+15
The end signature was defined in wakeup_asm.S as it originally came from the ACPI wakeup code. However, we rely on the existence of the .signature section to expand .bss, otherwise we would have to include code to explicitly zero the .bss depending on the configuration. Since the expanded .bss is just in .init.data anyway, it's easier to always have it expanded. This fixes failures when compiled without CONFIG_ACPI_SLEEP. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
2012-05-16x86, realmode: Change EFER to a single u64 fieldH. Peter Anvin2-5/+4
Change EFER to be a single u64 field instead of two u32 fields; change the order to maintain alignment. Note that on x86-64 cr4 is really also a 64-bit quantity, although we can only set the low 32 bits from the trampoline code since it is still executing in 32-bit mode at that point. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
2012-05-16x86, realmode: Move kernel/realmode.c to realmode/init.cH. Peter Anvin2-0/+117
Keep all the realmode code together, including initialization (only the rm/ subdirectory is actually built as real-mode code, anyway.) Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
2012-05-16x86, realmode: Move not-common bits out of trampoline_common.SH. Peter Anvin3-35/+33
Move the bits that aren't actually common out of trampoline_common.S and into the arch-specific files. Furthermore, make sure the page directory is first in the .bss section for trampoline_64.S in order to not waste an entire page of memory. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
2012-05-10x86, realmode: Fix no cache bits test in reboot_32.SJarkko Sakkinen1-1/+1
Before the new real-mode code infrastructure %edx was used for testing CD and NW bits with andl in order to decide whether to flush the processor caches or not. The value of cr0 was also stored in %eax, which was later used to set cr0 after masking out lower byte (except TS bit) in order to enter real-mode. In the new real-mode code infrastructure we wanted to keep input parameter in %eax so we are using %edx for both cr0 cases. This has caused regression since andl overwrites the value of %edx. This patch fixes the issue by replacing andl with testl, which is essentially andl without writing result to the register. Special thanks to Paolo Bonzini for noting this and proposing a fix. Reported-and-tested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336633898-23743-1-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-09x86, realmode: Make sure all generated files are listed in targetsH. Peter Anvin1-7/+13
Kbuild expects all generated files to be listed in the targets variable. If it isn't, weird things happen. Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336595106-21135-1-git-send-email-jarkko.sakkinen@intel.com
2012-05-09x86, realmode: build fix: remove duplicate buildJarkko Sakkinen2-5/+2
Real-mode binary was built twice. This patch fixes the issue by making realmode.relocs as target for realmode.bin. [ hpa: removed the direct dependency on realmode.relocs in arch/x86/realmode/Makefile ] Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336595106-21135-1-git-send-email-jarkko.sakkinen@intel.com Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: read cr4 and EFER from kernel for 64-bit trampolineJarkko Sakkinen3-25/+27
This patch changes 64-bit trampoline so that CR4 and EFER are provided by the kernel instead of using fixed values. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-24-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: move relocs from scripts/ to arch/x86/toolsJarkko Sakkinen1-1/+1
Moved relocs tool from scripts/ to arch/x86/tools because it is architecture specific script. Added new target archscripts that can be used to build scripts needed building an architecture. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-22-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Michal Marek <mmarek@suse.cz>
2012-05-08x86, realmode: header for trampoline codeJarkko Sakkinen5-63/+51
Added header for trampoline code that can be used to supply input data to it. This makes interface between real mode code and kernel cleaner and simpler. Replaced two confusing pointers to level4 pgt in trampoline_64.S with a single pointer to the beginning of the page table. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-21-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: flattened rm hierachyJarkko Sakkinen20-51/+21
Simplified hierarchy under rm directory to a flat directory because it is not anymore really justified to have own directory for wakeup code. It only adds more complexity. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-20-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: don't copy real_mode_headerJarkko Sakkinen3-2/+2
Replaced copying of real_mode_header with a pointer to beginning of RM memory. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-19-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: fix 64-bit wakeup sequenceJarkko Sakkinen8-106/+109
There were number of issues in wakeup sequence: - Wakeup stack was placed in hardcoded address. - NX bit in EFER was not enabled. - Initialization incorrectly set physical address of secondary_startup_64. - Some alignment issues. This patch fixes these issues and in addition: - Unifies coding conventions in .S files. - Sets alignments of code and data right. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-18-git-send-email-jarkko.sakkinen@intel.com Originally-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Len Brown <len.brown@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: Fix always-zero test in reboot_32.SH. Peter Anvin1-1/+1
A test instruction is an "and", and an and with zero is always zero. This would cause us to always take the BIOS path, not the APM path, in case anyone actually cares... Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-17-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Move trampoline_*.S early in the link orderH. Peter Anvin1-1/+1
Move trampoline_*.S earlier in the link order so it ends up being first in the text segment; since the SIPI vector requires 4K alignment it otherwise ends up padding the .text segment with that much completely unnecessarily. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-16-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Replace open-coded ljmpw with a macroH. Peter Anvin5-16/+25
We cannot code an ljmpw to the real-mode segment directly, because gas refuses to assemble an ljmp with a symbolic segment. Instead of open-coding it everywhere, define a macro and use it for this case. This is specifically an ljmpw from a 16-bit segment. This is okay, as one should never enter real mode from a 32-bit segment: if one do, the CPU ends up in a bizarre (and useless) mode sometimes called "unreal mode" where segments behave like real mode but the default address and operand sizes is 32 bits. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-15-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Remove indirect jumps in trampoline_32 and wakeup_asmH. Peter Anvin2-12/+18
Remove indirect jumps in trampoline_32.S and the 32-bit part of wakeup_asm.S. There exist systems which are known to do weird things if an SMI comes in right after a mode switch, and the safest way to deal with it is to always follow with a simple absolute far jump. In the 64-bit code we then to a register indirect near jump; follow that pattern for the 32-bit code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-14-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Remove indirect jumps in trampoline_64.SH. Peter Anvin1-13/+2
Remove indirect jumps in trampoline_64.S which are no longer necessary: the realmode code can relocate the absolute jumps correctly from the start. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-13-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Align .data section in trampoline_32.SH. Peter Anvin1-1/+1
Specify the alignment of the .data section in trampoline_32.S. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-12-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Move bits to the proper sections in trampoline_64.SH. Peter Anvin1-4/+6
Move various bits to the sections they really belong in in trampoline_64.S. Use GLOBAL() rather than ENTRY() for data objects: ENTRY() should only be used with code and forces alignment to 16 bytes. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-11-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Add .text64 section, make barrier symbols absoluteH. Peter Anvin1-3/+8
Add a .text64 section. The purpose of this is to keep 16-, 32- and 64-bit code segregated into separate sections, mainly to keep disassembly sane. Move barrier symbols out of sections to avoid the "symbol in empty section" problem in some versions of GNU ld. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-10-git-send-email-jarkko.sakkinen@intel.com
2012-05-08x86, realmode: Move ACPI wakeup to unified realmode codeJarkko Sakkinen15-0/+368
Migrated ACPI wakeup code to the real-mode blob. Code existing in .x86_trampoline can be completely removed. Static descriptor table in wakeup_asm.S is courtesy of H. Peter Anvin. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-7-git-send-email-jarkko.sakkinen@intel.com Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Len Brown <len.brown@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: Move SMP trampoline to unified realmode codeJarkko Sakkinen4-0/+273
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>
2012-05-08x86, realmode: Move reboot_32.S to unified realmode codeJarkko Sakkinen3-0/+138
Migrated reboot_32.S from x86_trampoline to the real-mode blob. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-5-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-08x86, realmode: realmode.bin infrastructureJarkko Sakkinen6-0/+188
Create realmode.bin and realmode.relocs files. Piggy pack them into relocatable object that will be included into .init.data section of the main kernel image. The first file includes binary image of the real-mode code. The latter file includes all relocations. The layout of the binary image is specified in realmode.lds.S. The makefile generates pa_ prefixed symbols for each exported global. These are used in 32-bit code and in realmode header to define symbols that need to be relocated. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-3-git-send-email-jarkko.sakkinen@intel.com Originally-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>