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2020-06-20x86_64: Fix jiffies ODR violationBob Haarman
commit d8ad6d39c35d2b44b3d48b787df7f3359381dcbf upstream. 'jiffies' and 'jiffies_64' are meant to alias (two different symbols that share the same address). Most architectures make the symbols alias to the same address via a linker script assignment in their arch/<arch>/kernel/vmlinux.lds.S: jiffies = jiffies_64; which is effectively a definition of jiffies. jiffies and jiffies_64 are both forward declared for all architectures in include/linux/jiffies.h. jiffies_64 is defined in kernel/time/timer.c. x86_64 was peculiar in that it wasn't doing the above linker script assignment, but rather was: 1. defining jiffies in arch/x86/kernel/time.c instead via the linker script. 2. overriding the symbol jiffies_64 from kernel/time/timer.c in arch/x86/kernel/vmlinux.lds.s via 'jiffies_64 = jiffies;'. As Fangrui notes: In LLD, symbol assignments in linker scripts override definitions in object files. GNU ld appears to have the same behavior. It would probably make sense for LLD to error "duplicate symbol" but GNU ld is unlikely to adopt for compatibility reasons. This results in an ODR violation (UB), which seems to have survived thus far. Where it becomes harmful is when; 1. -fno-semantic-interposition is used: As Fangrui notes: Clang after LLVM commit 5b22bcc2b70d ("[X86][ELF] Prefer to lower MC_GlobalAddress operands to .Lfoo$local") defaults to -fno-semantic-interposition similar semantics which help -fpic/-fPIC code avoid GOT/PLT when the referenced symbol is defined within the same translation unit. Unlike GCC -fno-semantic-interposition, Clang emits such relocations referencing local symbols for non-pic code as well. This causes references to jiffies to refer to '.Ljiffies$local' when jiffies is defined in the same translation unit. Likewise, references to jiffies_64 become references to '.Ljiffies_64$local' in translation units that define jiffies_64. Because these differ from the names used in the linker script, they will not be rewritten to alias one another. 2. Full LTO Full LTO effectively treats all source files as one translation unit, causing these local references to be produced everywhere. When the linker processes the linker script, there are no longer any references to jiffies_64' anywhere to replace with 'jiffies'. And thus '.Ljiffies$local' and '.Ljiffies_64$local' no longer alias at all. In the process of porting patches enabling Full LTO from arm64 to x86_64, spooky bugs have been observed where the kernel appeared to boot, but init doesn't get scheduled. Avoid the ODR violation by matching other architectures and define jiffies only by linker script. For -fno-semantic-interposition + Full LTO, there is no longer a global definition of jiffies for the compiler to produce a local symbol which the linker script won't ensure aliases to jiffies_64. Fixes: 40747ffa5aa8 ("asmlinkage: Make jiffies visible") Reported-by: Nathan Chancellor <natechancellor@gmail.com> Reported-by: Alistair Delva <adelva@google.com> Debugged-by: Nick Desaulniers <ndesaulniers@google.com> Debugged-by: Sami Tolvanen <samitolvanen@google.com> Suggested-by: Fangrui Song <maskray@google.com> Signed-off-by: Bob Haarman <inglorion@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # build+boot on Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: stable@vger.kernel.org Link: https://github.com/ClangBuiltLinux/linux/issues/852 Link: https://lkml.kernel.org/r/20200602193100.229287-1-inglorion@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-10x86/time: Correct the attribute on jiffies' definitionNathan Chancellor
commit 53c13ba8ed39e89f21a0b98f4c8a241bb44e483d upstream. Clang warns that the declaration of jiffies in include/linux/jiffies.h doesn't match the definition in arch/x86/time/kernel.c: arch/x86/kernel/time.c:29:42: warning: section does not match previous declaration [-Wsection] __visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES; ^ ./include/linux/cache.h:49:4: note: expanded from macro '__cacheline_aligned' __section__(".data..cacheline_aligned"))) ^ ./include/linux/jiffies.h:81:31: note: previous attribute is here extern unsigned long volatile __cacheline_aligned_in_smp __jiffy_arch_data jiffies; ^ ./arch/x86/include/asm/cache.h:20:2: note: expanded from macro '__cacheline_aligned_in_smp' __page_aligned_data ^ ./include/linux/linkage.h:39:29: note: expanded from macro '__page_aligned_data' #define __page_aligned_data __section(.data..page_aligned) __aligned(PAGE_SIZE) ^ ./include/linux/compiler_attributes.h:233:56: note: expanded from macro '__section' #define __section(S) __attribute__((__section__(#S))) ^ 1 warning generated. The declaration was changed in commit 7c30f352c852 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp") but wasn't updated here. Make them match so Clang no longer warns. Fixes: 7c30f352c852 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181013005311.28617-1-natechancellor@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-23x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'Andy Lutomirski
user_mode_vm() and user_mode() are now the same. Change all callers of user_mode_vm() to user_mode(). The next patch will remove the definition of user_mode_vm. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org [ Merged to a more recent kernel. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28x86_64/vdso: Remove jiffies from the vvar pageAndy Lutomirski
I think that the jiffies vvar was once used for the vgetcpu cache. That code is long gone, so let's just make jiffies be a normal variable. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/fcfee6f8749af14d96373a9e2656354ad0b95499.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-25x86: Fix non-PC platform kernel crash on boot due to NULL dereferenceAndy Shevchenko
Upstream commit: 95d76acc7518d5 ("x86, irq: Count legacy IRQs by legacy_pic->nr_legacy_irqs instead of NR_IRQS_LEGACY") removed reserved interrupts for the platforms that do not have a legacy IOAPIC. Which breaks the boot on Intel MID platforms such as Medfield: BUG: unable to handle kernel NULL pointer dereference at 0000003a IP: [<c107079a>] setup_irq+0xf/0x4d [ 0.000000] *pdpt = 0000000000000000 *pde = 9bbf32453167e510 The culprit is an uncoditional setting of IRQ2 which is used as cascade IRQ on legacy platforms. It seems we have to check if we have enough legacy IRQs reserved before we can call setup_irq(). The fix adds such check in native_init_IRQ() and in setup_default_timer_irq(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: David Cohen <david.a.cohen@linux.intel.com> Link: http://lkml.kernel.org/r/1405931920-12871-1-git-send-email-andriy.shevchenko@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-01Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq code updates from Thomas Gleixner: "The irq department proudly presents: - Another tree wide sweep of irq infrastructure abuse. Clear winner of the trainwreck engineering contest was: #include "../../../kernel/irq/settings.h" - Tree wide update of irq_set_affinity() callbacks which miss a cpu online check when picking a single cpu out of the affinity mask. - Tree wide consolidation of interrupt statistics. - Updates to the threaded interrupt infrastructure to allow explicit wakeup of the interrupt thread and a variant of synchronize_irq() which synchronizes only the hard interrupt handler. Both are needed to replace the homebrewn thread handling in the mmc/sdhci code. - New irq chip callbacks to allow proper support for GPIO based irqs. The GPIO based interrupts need to request/release GPIO resources from request/free_irq. - A few new ARM interrupt chips. No revolutionary new hardware, just differently wreckaged variations of the scheme. - Small improvments, cleanups and updates all over the place" I was hoping that that trainwreck engineering contest was a April Fools' joke. But no. * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (68 commits) irqchip: sun7i/sun6i: Disable NMI before registering the handler ARM: sun7i/sun6i: dts: Fix IRQ number for sun6i NMI controller ARM: sun7i/sun6i: irqchip: Update the documentation ARM: sun7i/sun6i: dts: Add NMI irqchip support ARM: sun7i/sun6i: irqchip: Add irqchip driver for NMI controller genirq: Export symbol no_action() arm: omap: Fix typo in ams-delta-fiq.c m68k: atari: Fix the last kernel_stat.h fallout irqchip: sun4i: Simplify sun4i_irq_ack irqchip: sun4i: Use handle_fasteoi_irq for all interrupts genirq: procfs: Make smp_affinity values go+r softirq: Add linux/irq.h to make it compile again m68k: amiga: Add linux/irq.h to make it compile again irqchip: sun4i: Don't ack IRQs > 0, fix acking of IRQ 0 irqchip: sun4i: Fix a comment about mask register initialization irqchip: sun4i: Fix irq 0 not working genirq: Add a new IRQCHIP_EOI_THREADED flag genirq: Document IRQCHIP_ONESHOT_SAFE flag ARM: sunxi: dt: Convert to the new irq controller compatibles irqchip: sunxi: Change compatibles ...
2014-03-04x86: Remove deprecated IRQF_DISABLEDMichael Opdenacker
This patch removes the IRQF_DISABLED flag from x86 architecture code. It's a NOOP since 2.6.35 and it will be removed one day. Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Cc: venki@google.com Link: http://lkml.kernel.org/r/1393965305-17248-1-git-send-email-michael.opdenacker@free-electrons.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-13asmlinkage: Make jiffies visibleAndi Kleen
Jiffies is referenced by the linker script, so it has to be visible. Handled both the generic and the x86 version. Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1391845930-28580-3-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-17MCA: delete all remaining traces of microchannel bus support.Paul Gortmaker
Hardware with MCA bus is limited to 386 and 486 class machines that are now 20+ years old and typically with less than 32MB of memory. A quick search on the internet, and you see that even the MCA hobbyist/enthusiast community has lost interest in the early 2000 era and never really even moved ahead from the 2.4 kernels to the 2.6 series. This deletes anything remaining related to CONFIG_MCA from core kernel code and from the x86 architecture. There is no point in carrying this any further into the future. One complication to watch for is inadvertently scooping up stuff relating to machine check, since there is overlap in the TLA name space (e.g. arch/x86/boot/mca.c). Cc: Thomas Gleixner <tglx@linutronix.de> Cc: James Bottomley <JBottomley@Parallels.com> Cc: x86@kernel.org Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-27x86/time: Eliminate unused irq0_irqs counterJan Beulich
As of v2.6.38 this counter is being maintained without ever being read. Signed-off-by: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/4F4787930200007800074A10@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-31x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULEPaul Gortmaker
These files were implicitly getting EXPORT_SYMBOL via device.h which was including module.h, but that will be fixed up shortly. By fixing these now, we can avoid seeing things like: arch/x86/kernel/rtc.c:29: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’ arch/x86/kernel/pci-dma.c:20: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’ arch/x86/kernel/e820.c:69: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL_GPL’ [ with input from Randy Dunlap <rdunlap@xenotime.net> and also from Stephen Rothwell <sfr@canb.auug.org.au> ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-06-09i8253: Create linux/i8253.h and use it in all 8253 related filesRalf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Link: http://lkml.kernel.org/r/20110601180610.054254048@duck.linux-mips.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> arch/arm/mach-footbridge/isa-timer.c | 2 +- arch/mips/cobalt/time.c | 2 +- arch/mips/jazz/irq.c | 2 +- arch/mips/kernel/i8253.c | 2 +- arch/mips/mti-malta/malta-time.c | 2 +- arch/mips/sgi-ip22/ip22-time.c | 2 +- arch/mips/sni/time.c | 2 +- arch/x86/kernel/apic/apic.c | 2 +- arch/x86/kernel/apm_32.c | 2 +- arch/x86/kernel/hpet.c | 2 +- arch/x86/kernel/i8253.c | 2 +- arch/x86/kernel/time.c | 2 +- drivers/block/hd.c | 2 +- drivers/clocksource/i8253.c | 2 +- drivers/input/gameport/gameport.c | 2 +- drivers/input/joystick/analog.c | 2 +- drivers/input/misc/pcspkr.c | 2 +- include/linux/i8253.h | 11 +++++++++++ sound/drivers/pcsp/pcsp.h | 2 +- 19 files changed, 29 insertions(+), 18 deletions(-)
2011-05-24x86-64: Clean up vdso/kernel shared variablesAndy Lutomirski
Variables that are shared between the vdso and the kernel are currently a bit of a mess. They are each defined with their own magic, they are accessed differently in the kernel, the vsyscall page, and the vdso, and one of them (vsyscall_clock) doesn't even really exist. This changes them all to use a common mechanism. All of them are delcared in vvar.h with a fixed address (validated by the linker script). In the kernel (as before), they look like ordinary read-write variables. In the vsyscall page and the vdso, they are accessed through a new macro VVAR, which gives read-only access. The vdso is now loaded verbatim into memory without any fixups. As a side bonus, access from the vdso is faster because a level of indirection is removed. While we're at it, pack jiffies and vgetcpu_mode into the same cacheline. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C7357882fbb51fa30491636a7b6528747301b7ee9.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-11-18x86, nmi_watchdog: Remove all stub function calls from old nmi_watchdogDon Zickus
Now that the bulk of the old nmi_watchdog is gone, remove all the stub variables and hooks associated with it. This touches lots of files mainly because of how the io_apic nmi_watchdog was implemented. Now that the io_apic nmi_watchdog is forever gone, remove all its fingers. Most of this code was not being exercised by virtue of nmi_watchdog != NMI_IO_APIC, so there shouldn't be anything to risky here. Signed-off-by: Don Zickus <dzickus@redhat.com> Cc: fweisbec@gmail.com Cc: gorcunov@openvz.org LKML-Reference: <1289578944-28564-3-git-send-email-dzickus@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-16x86: Convert i8259_lock to raw_spinlockThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-10-12x86: fix kernel panic on 32 bits when profilingH. Peter Anvin
Latest kernel has a kernel panic in booting on i386 machine when profile=2 setting in cmdline. It is due to 'sp' being incorrect in profile_pc(). BUG: unable to handle kernel NULL pointer dereference at 00000246 IP: [<c01288b6>] profile_pc+0x2a/0x48 *pde = 00000000 Oops: 0000 [#1] SMP This differs from the original version by Alex Shi in that we use the kernel_stack_pointer() inline already defined in <asm/ptrace.h> for this purpose, instead of #ifdef. Originally-by: Alex Shi <alex.shi@intel.com> Cc: "Chen, Tim C" <tim.c.chen@intel.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-24cpumask: remove last assignment to mask field of struct irqaction.Rusty Russell
This snuck in after the patch which removed all the others. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@elte.hu>
2009-09-16x86: platform: Fix section annotationsThomas Gleixner
init_IRQ() and x86_late_time_init() are missing __init annotations. The x86 platform ops variables are annotated, but the annotation needs to be put between the variable name and the "=" of the initializer. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31x86: Move tsc_init to late_time_initThomas Gleixner
We do not need the TSC before late_time_init. Move the tsc_init to the late time init code so we can also utilize HPET for calibration (which we claimed to do but never did except in some older kernel version). This also helps Moorestown to calibrate the TSC with the AHBT timer which needs to be initialized in late_time_init like HPET. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31x86: Replace the now identical time_32/64.c by time.cThomas Gleixner
Remove the redundant copy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>