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2015-06-23Merge branch 'x86-core-for-linus' of ↵Linus Torvalds41-0/+7155
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Ingo Molnar: "There were so many changes in the x86/asm, x86/apic and x86/mm topics in this cycle that the topical separation of -tip broke down somewhat - so the result is a more traditional architecture pull request, collected into the 'x86/core' topic. The topics were still maintained separately as far as possible, so bisectability and conceptual separation should still be pretty good - but there were a handful of merge points to avoid excessive dependencies (and conflicts) that would have been poorly tested in the end. The next cycle will hopefully be much more quiet (or at least will have fewer dependencies). The main changes in this cycle were: * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas Gleixner) - This is the second and most intrusive part of changes to the x86 interrupt handling - full conversion to hierarchical interrupt domains: [IOAPIC domain] ----- | [MSI domain] --------[Remapping domain] ----- [ Vector domain ] | (optional) | [HPET MSI domain] ----- | | [DMAR domain] ----------------------------- | [Legacy domain] ----------------------------- This now reflects the actual hardware and allowed us to distangle the domain specific code from the underlying parent domain, which can be optional in the case of interrupt remapping. It's a clear separation of functionality and removes quite some duct tape constructs which plugged the remap code between ioapic/msi/hpet and the vector management. - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt injection into guests (Feng Wu) * x86/asm changes: - Tons of cleanups and small speedups, micro-optimizations. This is in preparation to move a good chunk of the low level entry code from assembly to C code (Denys Vlasenko, Andy Lutomirski, Brian Gerst) - Moved all system entry related code to a new home under arch/x86/entry/ (Ingo Molnar) - Removal of the fragile and ugly CFI dwarf debuginfo annotations. Conversion to C will reintroduce many of them - but meanwhile they are only getting in the way, and the upstream kernel does not rely on them (Ingo Molnar) - NOP handling refinements. (Borislav Petkov) * x86/mm changes: - Big PAT and MTRR rework: making the code more robust and preparing to phase out exposing direct MTRR interfaces to drivers - in favor of using PAT driven interfaces (Toshi Kani, Luis R Rodriguez, Borislav Petkov) - New ioremap_wt()/set_memory_wt() interfaces to support Write-Through cached memory mappings. This is especially important for good performance on NVDIMM hardware (Toshi Kani) * x86/ras changes: - Add support for deferred errors on AMD (Aravind Gopalakrishnan) This is an important RAS feature which adds hardware support for poisoned data. That means roughly that the hardware marks data which it has detected as corrupted but wasn't able to correct, as poisoned data and raises an APIC interrupt to signal that in the form of a deferred error. It is the OS's responsibility then to take proper recovery action and thus prolonge system lifetime as far as possible. - Add support for Intel "Local MCE"s: upcoming CPUs will support CPU-local MCE interrupts, as opposed to the traditional system- wide broadcasted MCE interrupts (Ashok Raj) - Misc cleanups (Borislav Petkov) * x86/platform changes: - Intel Atom SoC updates ... and lots of other cleanups, fixlets and other changes - see the shortlog and the Git log for details" * 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits) x86/hpet: Use proper hpet device number for MSI allocation x86/hpet: Check for irq==0 when allocating hpet MSI interrupts x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail genirq: Prevent crash in irq_move_irq() genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain iommu, x86: Properly handle posted interrupts for IOMMU hotplug iommu, x86: Provide irq_remapping_cap() interface iommu, x86: Setup Posted-Interrupts capability for Intel iommu iommu, x86: Add cap_pi_support() to detect VT-d PI capability iommu, x86: Avoid migrating VT-d posted interrupts iommu, x86: Save the mode (posted or remapped) of an IRTE iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip iommu: dmar: Provide helper to copy shared irte fields iommu: dmar: Extend struct irte for VT-d Posted-Interrupts iommu: Add new member capability to struct irq_remap_ops x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry() ...
2015-06-10x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode codeAndy Lutomirski1-8/+31
The error_entry/error_exit code to handle gsbase and whether we return to user mdoe was a mess: - error_sti was misnamed. In particular, it did not enable interrupts. - Error handling for gs_change was hopelessly tangled the normal usermode path. Separate it out. This saves a branch in normal entries from kernel mode. - The comments were bad. Fix it up. As a nice side effect, there's now a code path that happens on error entries from user mode. We'll use it soon. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/f1be898ab93360169fb845ab85185948832209ee.1433878454.git.luto@kernel.org [ Prettified it, clarified comments some more. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-10x86/asm/entry/32: Shorten __audit_syscall_entry() args preparationDenys Vlasenko1-9/+18
We use three MOVs to swap edx and ecx. We can use one XCHG instead. Expand the comments. It's difficult to keep track which arg# every register corresponds to, so spell it out. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433876051-26604-3-git-send-email-dvlasenk@redhat.com [ Expanded the comments some more. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-10x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()Denys Vlasenko1-8/+12
Here it is not obvious why we load pt_regs->cx to %esi etc. Lets improve comments. Explain that here we combine two things: first, we reload registers since some of them are clobbered by the C function we just called; and we also convert 32-bit syscall params to 64-bit C ABI, because we are going to jump back to syscall dispatch code. Move reloading of 6th argument into the macro instead of having it after each of two macro invocations. No actual code changes here. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433876051-26604-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-10x86/asm/entry/32: Fix fallout from the R9 trick removal in the SYSCALL codeDenys Vlasenko1-1/+1
I put %ebp restoration code too late. Under strace, it is not reached and %ebp is not restored upon return to userspace. This is the fix. Run-tested. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433876051-26604-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-09x86/asm/entry: Clean up entry*.S style, final bitsDenys Vlasenko2-16/+16
A few bits were missed. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-09x86/asm/entry: (Re-)rename __NR_entry_INT80_compat_max to ↵Ingo Molnar1-3/+3
__NR_syscall_compat_max Brian Gerst noticed that I did a weird rename in the following commit: b2502b418e63 ("x86/asm/entry: Untangle 'system_call' into two entry points: entry_SYSCALL_64 and entry_INT80_32") which renamed __NR_ia32_syscall_max to __NR_entry_INT80_compat_max. Now the original name was a misnomer, but the new one is a misnomer as well, as all the 32-bit compat syscall entry points (sysenter, syscall) share the system call table, not just the INT80 based one. Rename it to __NR_syscall_compat_max. Reported-by: Brian Gerst <brgerst@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-09x86/asm/entry/32: Reinstate clearing of pt_regs->r8..r11 on EFAULT pathDenys Vlasenko1-6/+2
I broke this recently when I changed pt_regs->r8..r11 clearing logic in INT 80 code path. There is a branch from SYSENTER/SYSCALL code to INT 80 code: if we fail to retrieve arg6, we return EFAULT. Before this patch, in this case we don't clear pt_regs->r8..r11. This patch fixes this. The resulting code is smaller and simpler. While at it, remove incorrect comment about syscall dispatching CALL insn: it does not use RIP-relative addressing form (the comment was meant to be "TODO: make this rip-relative", and morphed since then, dropping "TODO"). Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433701470-28800-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08x86/asm/entry/64: Clean up entry_64.SIngo Molnar1-416/+404
Make the 64-bit syscall entry code a bit more readable: - use consistent assembly coding style similar to the other entry_*.S files - remove old comments that are not true anymore - eliminate whitespace noise - use consistent vertical spacing - fix various comments - reorganize entry point generation tables to be more readable No code changed: # arch/x86/entry/entry_64.o: text data bss dec hex filename 12282 0 0 12282 2ffa entry_64.o.before 12282 0 0 12282 2ffa entry_64.o.after md5: cbab1f2d727a2a8a87618eeb79f391b7 entry_64.o.before.asm cbab1f2d727a2a8a87618eeb79f391b7 entry_64.o.after.asm Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08Merge branch 'x86/asm' into x86/core, to prepare for new patchIngo Molnar41-0/+7139
Collect all changes to arch/x86/entry/entry_64.S, before applying patch that changes most of the file. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08x86/asm/entry/32: Clean up entry_32.SIngo Molnar1-571/+570
Make the 32-bit syscall entry code a bit more readable: - use consistent assembly coding style similar to entry_64.S - remove old comments that are not true anymore - eliminate whitespace noise - use consistent vertical spacing - fix various comments No code changed: # arch/x86/entry/entry_32.o: text data bss dec hex filename 6025 0 0 6025 1789 entry_32.o.before 6025 0 0 6025 1789 entry_32.o.after md5: f3fa16b2b0dca804f052deb6b30ba6cb entry_32.o.before.asm f3fa16b2b0dca804f052deb6b30ba6cb entry_32.o.after.asm Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08x86/asm/entry: Untangle 'system_call' into two entry points: ↵Ingo Molnar2-7/+7
entry_SYSCALL_64 and entry_INT80_32 The 'system_call' entry points differ starkly between native 32-bit and 64-bit kernels: on 32-bit kernels it defines the INT 0x80 entry point, while on 64-bit it's the SYSCALL entry point. This is pretty confusing when looking at generic code, and it also obscures the nature of the entry point at the assembly level. So unangle this by splitting the name into its two uses: system_call (32) -> entry_INT80_32 system_call (64) -> entry_SYSCALL_64 As per the generic naming scheme for x86 system call entry points: entry_MNEMONIC_qualifier where 'qualifier' is one of _32, _64 or _compat. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08x86/asm/entry: Untangle 'ia32_sysenter_target' into two entry points: ↵Ingo Molnar2-7/+7
entry_SYSENTER_32 and entry_SYSENTER_compat So the SYSENTER instruction is pretty quirky and it has different behavior depending on bitness and CPU maker. Yet we create a false sense of coherency by naming it 'ia32_sysenter_target' in both of the cases. Split the name into its two uses: ia32_sysenter_target (32) -> entry_SYSENTER_32 ia32_sysenter_target (64) -> entry_SYSENTER_compat As per the generic naming scheme for x86 system call entry points: entry_MNEMONIC_qualifier where 'qualifier' is one of _32, _64 or _compat. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08x86/asm/entry: Rename compat syscall entry pointsIngo Molnar2-7/+7
Rename the following system call entry points: ia32_cstar_target -> entry_SYSCALL_compat ia32_syscall -> entry_INT80_compat The generic naming scheme for x86 system call entry points is: entry_MNEMONIC_qualifier where 'qualifier' is one of _32, _64 or _compat. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07x86/asm/entry/64/compat: Rename ia32entry.S -> entry_64_compat.SIngo Molnar3-2/+2
So we now have the following system entry code related files, which define the following system call instruction and other entry paths: entry_32.S # 32-bit binaries on 32-bit kernels entry_64.S # 64-bit binaries on 64-bit kernels entry_64_compat.S # 32-bit binaries on 64-bit kernels Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Remove unnecessary optimization in stub32_cloneDenys Vlasenko1-7/+6
Really swap arguments #4 and #5 in stub32_clone instead of "optimizing" it into a move. Yes, tls_val is currently unused. Yes, on some CPUs XCHG is a little bit more expensive than MOV. But a cycle or two on an expensive syscall like clone() is way below noise floor, and this optimization is simply not worth the obfuscation of logic. [ There's also ongoing work on the clone() ABI by Josh Triplett that will depend on this change later on. ] Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433339930-20880-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Explain the stub32_clone logicDenys Vlasenko1-0/+8
The reason for copying of %r8 to %rcx is quite non-obvious. Add a comment which explains why it is done. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433339930-20880-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Improve code readabilityIngo Molnar1-141/+146
Make the 64-bit compat 32-bit syscall entry code a bit more readable: - eliminate whitespace noise - use consistent vertical spacing - use consistent assembly coding style similar to entry_64.S - fix various comments No code changed: arch/x86/entry/ia32entry.o: text data bss dec hex filename 1391 0 0 1391 56f ia32entry.o.before 1391 0 0 1391 56f ia32entry.o.after md5: f28501dcc366e68b557313942c6496d6 ia32entry.o.before.asm f28501dcc366e68b557313942c6496d6 ia32entry.o.after.asm Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Do not use R9 in SYSCALL32 entry pointDenys Vlasenko1-11/+8
SYSENTER and SYSCALL 32-bit entry points differ in handling of arg2 and arg6. SYSENTER: * ecx arg2 * ebp user stack * 0(%ebp) arg6 SYSCALL: * ebp arg2 * esp user stack * 0(%esp) arg6 Sysenter code loads 0(%ebp) to %ebp right away. (This destroys %ebp. It means we do not preserve it on return. It's not causing problems since userspace VDSO code does not depend on it, and SYSENTER insn can't be sanely used outside of VDSO). Syscall code loads 0(%ebp) to %r9. This allows to eliminate one MOV insn (r9 is a register where arg6 should be for 64-bit ABI), but on audit/ptrace code paths this requires juggling of r9 and ebp: (1) ptrace expects arg6 to be in pt_regs->bp; (2) r9 is callee-clobbered register and needs to be saved/restored around calls to C functions. This patch changes syscall code to load 0(%ebp) to %ebp, making it more similar to sysenter code. It's a bit smaller: text data bss dec hex filename 1407 0 0 1407 57f ia32entry.o.before 1391 0 0 1391 56f ia32entry.o To preserve ABI compat, we restore ebp on exit. Run-tested. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433336169-18964-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Open-code LOAD_ARGS32Denys Vlasenko1-25/+29
This macro is small, has only three callsites, and one of them is slightly different using a conditional parameter. A few saved lines aren't worth the resulting obfuscation. Generated machine code is identical. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433271842-9139-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Open-code CLEAR_RREGSDenys Vlasenko1-13/+20
This macro is small, has only four callsites, and one of them is slightly different using a conditional parameter. A few saved lines aren't worth the resulting obfuscation. Generated machine code is identical. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> [ Added comments. ] Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433271842-9139-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/32: Simplify the zeroing of pt_regs->r8..r11 in the int80 code ↵Denys Vlasenko1-4/+9
path 32-bit syscall entry points do not save the complete pt_regs struct, they leave some fields uninitialized. However, they must be careful to not leak uninitialized data in pt_regs->r8..r11 to ptrace users. CLEAR_RREGS macro is used to zero these fields out when needed. However, in the int80 code path this zeroing is unconditional. This patch simplifies it by storing zeroes there right away, when pt_regs is constructed on stack. This uses shorter instructions: text data bss dec hex filename 1423 0 0 1423 58f ia32entry.o.before 1407 0 0 1407 57f ia32entry.o Compile-tested. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1433266510-2938-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-05x86/asm/entry/64: Remove pointless jump to irq_returnAndy Lutomirski1-3/+1
INTERRUPT_RETURN turns into a jmp instruction. There's no need for extra indirection. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: <linux-kernel@vger.kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2f2318653dbad284a59311f13f08cea71298fd7c.1433449436.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-04x86/asm/entry: Move the vsyscall code to arch/x86/entry/vsyscall/Ingo Molnar8-2/+547
The vsyscall code is entry code too, so move it to arch/x86/entry/vsyscall/. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-04x86/asm/entry: Move the arch/x86/syscalls/ definitions to ↵Ingo Molnar5-0/+848
arch/x86/entry/syscalls/ The build time generated syscall definitions are entry code related, move them into the arch/x86/entry/ directory. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-04x86/asm/entry: Move arch/x86/include/asm/calling.h to arch/x86/entry/Ingo Molnar4-3/+246
asm/calling.h is private to the entry code, make this more apparent by moving it to the new arch/x86/entry/ directory. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-04x86/asm/entry: Move the 'thunk' functions to arch/x86/entry/Ingo Molnar3-2/+112
These are all calling x86 entry code functions, so move them close to other entry code. Change lib-y to obj-y: there's no real difference between the two as we don't really drop any of them during the linking stage, and obj-y is the more common approach for core kernel object code. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-03x86/asm/entry, x86/vdso: Move the vDSO code to arch/x86/entry/vdso/Ingo Molnar23-0/+2144
Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-03x86/asm/entry: Move the compat syscall entry code to arch/x86/entry/Ingo Molnar2-1/+526
Move the ia32entry.S file over into arch/x86/entry/. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-03x86/asm/entry: Move entry_64.S and entry_32.S to arch/x86/entry/Ingo Molnar3-0/+2695
Create a new directory hierarchy for the low level x86 entry code: arch/x86/entry/* This will host all the low level glue that is currently scattered all across arch/x86/. Start with entry_64.S and entry_32.S. Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>