linux/include/asm-generic/vmlinux.lds.h, branch v4.7

vmlinux.lds: account for destructor sections

2016-07-15T05:54:27Z

If CONFIG_KASAN is enabled and gcc is configured with --disable-initfini-array and/or gold linker is used, gcc emits .ctors/.dtors and .text.startup/.text.exit sections instead of .init_array/.fini_array. .dtors section is not explicitly accounted in the linker script and messes vvar/percpu layout. We want: ffffffff822bfd80 D _edata ffffffff822c0000 D __vvar_beginning_hack ffffffff822c0000 A __vvar_page ffffffff822c0080 0000000000000098 D vsyscall_gtod_data ffffffff822c1000 A __init_begin ffffffff822c1000 D init_per_cpu__irq_stack_union ffffffff822c1000 A __per_cpu_load ffffffff822d3000 D init_per_cpu__gdt_page We got: ffffffff8279a600 D _edata ffffffff8279b000 A __vvar_page ffffffff8279c000 A __init_begin ffffffff8279c000 D init_per_cpu__irq_stack_union ffffffff8279c000 A __per_cpu_load ffffffff8279e000 D __vvar_beginning_hack ffffffff8279e080 0000000000000098 D vsyscall_gtod_data ffffffff827ae000 D init_per_cpu__gdt_page This happens because __vvar_page and .vvar get different addresses in arch/x86/kernel/vmlinux.lds.S: . = ALIGN(PAGE_SIZE); __vvar_page = .; .vvar : AT(ADDR(.vvar) - LOAD_OFFSET) { /* work around gold bug 13023 */ __vvar_beginning_hack = .; Discard .dtors/.fini_array/.text.exit, since we don't call dtors. Merge .text.startup into init text. Link: http://lkml.kernel.org/r/1467386363-120030-1-git-send-email-dvyukov@google.com Signed-off-by: Dmitry Vyukov Reviewed-by: Andrey Ryabinin Cc: [4.0+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

x86/asm: Make sure verify_cpu() has a good stack

2016-04-13T09:52:19Z

04633df0c43d ("x86/cpu: Call verify_cpu() after having entered long mode too") added the call to verify_cpu() for sanitizing CPU configuration. The latter uses the stack minimally and it can happen that we land in startup_64() directly from a 64-bit bootloader. Then we want to use our own, known good stack. Do that. APs don't need this as the trampoline sets up a stack for them. Reported-by: Tom Lendacky Signed-off-by: Borislav Petkov Cc: Brian Gerst Cc: Linus Torvalds Cc: Mika Penttilä Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1459434062-31055-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar

arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections

2016-03-25T23:37:42Z

KASAN needs to know whether the allocation happens in an IRQ handler. This lets us strip everything below the IRQ entry point to reduce the number of unique stack traces needed to be stored. Move the definition of __irq_entry to so that the users don't need to pull in . Also introduce the __softirq_entry macro which is similar to __irq_entry, but puts the corresponding functions to the .softirqentry.text section. Signed-off-by: Alexander Potapenko Acked-by: Steven Rostedt Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Konstantin Serebryany Cc: Dmitry Chernenkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2016-03-17T20:53:25Z

Pull tty/serial updates from Greg KH: "Here's the big tty/serial driver pull request for 4.6-rc1. Lots of changes in here, Peter has been on a tear again, with lots of refactoring and bugs fixes, many thanks to the great work he has been doing. Lots of driver updates and fixes as well, full details in the shortlog. All have been in linux-next for a while with no reported issues" * tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (220 commits) serial: 8250: describe CONFIG_SERIAL_8250_RSA serial: samsung: optimize UART rx fifo access routine serial: pl011: add mark/space parity support serial: sa1100: make sa1100_register_uart_fns a function tty: serial: 8250: add MOXA Smartio MUE boards support serial: 8250: convert drivers to use up_to_u8250p() serial: 8250/mediatek: fix building with SERIAL_8250=m serial: 8250/ingenic: fix building with SERIAL_8250=m serial: 8250/uniphier: fix modular build Revert "drivers/tty/serial: make 8250/8250_ingenic.c explicitly non-modular" Revert "drivers/tty/serial: make 8250/8250_mtk.c explicitly non-modular" serial: mvebu-uart: initial support for Armada-3700 serial port serial: mctrl_gpio: Add missing module license serial: ifx6x60: avoid uninitialized variable use tty/serial: at91: fix bad offset for UART timeout register tty/serial: at91: restore dynamic driver binding serial: 8250: Add hardware dependency to RT288X option TTY, devpts: document pty count limiting tty: goldfish: support platform_device with id -1 drivers: tty: goldfish: Add device tree bindings ...

arch: Introduce post-init read-only memory

2016-02-22T07:51:38Z

One of the easiest ways to protect the kernel from attack is to reduce the internal attack surface exposed when a "write" flaw is available. By making as much of the kernel read-only as possible, we reduce the attack surface. Many things are written to only during __init, and never changed again. These cannot be made "const" since the compiler will do the wrong thing (we do actually need to write to them). Instead, move these items into a memory region that will be made read-only during mark_rodata_ro() which happens after all kernel __init code has finished. This introduces __ro_after_init as a way to mark such memory, and adds some documentation about the existing __read_mostly marking. This improves the security of the Linux kernel by marking formerly read-write memory regions as read-only on a fully booted up system. Based on work by PaX Team and Brad Spengler. Signed-off-by: Kees Cook Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brad Spengler Cc: Brian Gerst Cc: David Brown Cc: Denys Vlasenko Cc: Emese Revfy Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Mathias Krause Cc: Michael Ellerman Cc: PaX Team Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kernel-hardening@lists.openwall.com Cc: linux-arch Link: http://lkml.kernel.org/r/1455748879-21872-5-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar

earlycon: Use common framework for earlycon declarations

2016-02-07T06:07:37Z

Use a single common table of struct earlycon_id for both command line and devicetree. Re-define OF_EARLYCON_DECLARE() macro to instance a unique earlycon declaration (the declaration is only guaranteed to be unique within a compilation unit; separate compilation units must still use unique earlycon names). The semantics of OF_EARLYCON_DECLARE() is different; it declares an earlycon which can matched either on the command line or by devicetree. EARLYCON_DECLARE() is semantically unchanged; it declares an earlycon which is matched by command line only. Remove redundant instances of EARLYCON_DECLARE(). This enables all earlycons to properly initialize struct console with the appropriate name and index, which improves diagnostics and enables direct earlycon-to-console handoff. Acked-by: Rob Herring Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

clocksource / ACPI: Add probing infrastructure for ACPI-based clocksources

2015-10-01T00:18:38Z

DT enjoys a rather nice probing infrastructure for clocksources, while ACPI is so far stuck into a very distant past. This patch introduces a declarative API, allowing clocksources to be self-contained and be called when parsing the GTDT table. Signed-off-by: Marc Zyngier Acked-by: Thomas Gleixner Tested-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki

irqchip / ACPI: Add probing infrastructure for ACPI-based irqchips

2015-10-01T00:18:38Z

DT enjoys a rather nice probing infrastructure for irqchips, while ACPI is so far stuck into a very distant past. This patch introduces a declarative API, allowing irqchips to be self-contained and be called when a particular entry is matched in the MADT table. Signed-off-by: Marc Zyngier Acked-by: Catalin Marinas Reviewed-by: Hanjun Guo Acked-by: Thomas Gleixner Tested-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki

ACPI: Add early device probing infrastructure

2015-10-01T00:18:38Z

IRQ controllers and timers are the two types of device the kernel requires before being able to use the device driver model. ACPI so far lacks a proper probing infrastructure similar to the one we have with DT, where we're able to declare IRQ chips and clocksources inside the driver code, and let the core code pick it up and call us back on a match. This leads to all kind of really ugly hacks all over the arm64 code and even in the ACPI layer. In order to allow some basic probing based on the ACPI tables, introduce "struct acpi_probe_entry" which contains just enough data and callbacks to match a table, an optional subtable, and call a probe function. A driver can, at build time, register itself and expect being called if the right entry exists in the ACPI table. A acpi_probe_device_table() is provided, taking an identifier for a set of acpi_prove_entries, and iterating over the registered entries. Signed-off-by: Marc Zyngier Reviewed-by: Lorenzo Pieralisi Reviewed-by: Hanjun Guo Acked-by: Thomas Gleixner Tested-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki

kbuild: Fix .text.unlikely placement

2015-08-20T12:55:54Z

When building a kernel with .text.unlikely text the unlikely text for each translation unit was put next to the main .text code in the final vmlinux. The problem is that the linker doesn't allow more specific submatches of a section name in a different linker script statement after the main match. So we need to move them all into one line. With that change .text.unlikely is at the end of everything again. I also moved .text.hot into the same statement though, even though that's not strictly needed. Signed-off-by: Andi Kleen Signed-off-by: Michal Marek