kernel.git/arch/x86/kernel/vmlinux_64.lds.S, branch linux-2.6.30.y

x86/brk: put the brk reservations in their own section

2009-03-17T19:58:15Z

Impact: disambiguate real .bss variables from .brk storage Add a .brk section after the .bss section. This has no effect on the final vmlinux, but it more clearly distinguishes the space taken by actual .bss symbols, and the variable space reserved by .brk users. Signed-off-by: Jeremy Fitzhardinge

x86: allow extend_brk users to reserve brk space

2009-03-15T00:23:47Z

Impact: new interface; remove hard-coded limit Add RESERVE_BRK(name, size) macro to reserve space in the brk area. This should be a conservative (ie, larger) estimate of how much space might possibly be required from the brk area. Any unused space will be freed, so there's no real downside on making the reservation too large (within limits). The name should be unique within a given file, and somewhat descriptive. The C definition of RESERVE_BRK() ends up being more complex than one would expect to work around a cluster of gcc infelicities: The first attempt was to simply try putting __section(.brk_reservation) on a variable. This doesn't work because it ends up making it a @progbits section, which gets actual space allocated in the vmlinux executable. The second attempt was to emit the space into a section using asm, but gcc doesn't allow arguments to be passed to file-level asm() statements, making it hard to pass in the size. The final attempt is to wrap the asm() in a function to allow it to have arguments, and put the function itself into the .discard section, which vmlinux*.lds drops entirely from the emitted vmlinux. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: H. Peter Anvin

x86: add brk allocation for very, very early allocations

2009-03-14T22:37:14Z

Impact: new interface Add a brk()-like allocator which effectively extends the bss in order to allow very early code to do dynamic allocations. This is better than using statically allocated arrays for data in subsystems which may never get used. The space for brk allocations is in the bss ELF segment, so that the space is mapped properly by the code which maps the kernel, and so that bootloaders keep the space free rather than putting a ramdisk or something into it. The bss itself, delimited by __bss_stop, ends before the brk area (__brk_base to __brk_limit). The kernel text, data and bss is reserved up to __bss_stop. Any brk-allocated data is reserved separately just before the kernel pagetable is built, as that code allocates from unreserved spaces in the e820 map, potentially allocating from any unused brk memory. Ultimately any unused memory in the brk area is used in the general kernel memory pool. Initially the brk space is set to 1MB, which is probably much larger than any user needs (the largest current user is i386 head_32.S's code to build the pagetables to map the kernel, which can get fairly large with a big kernel image and no PSE support). So long as the system has sufficient memory for the bootloader to reserve the kernel+1MB brk, there are no bad effects resulting from an over-large brk. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: H. Peter Anvin

x86: make section delimiter symbols part of their section

2009-03-14T22:37:14Z

Impact: cleanup Move the symbols delimiting a section part of the section (section relative) rather than absolute. This avoids any unexpected gaps between the section-start symbol and the first data in the section, which could be caused by implicit alignment of the section data. It also makes the general form of vmlinux_64.lds.S consistent with vmlinux_32.lds.S. Signed-off-by: Jeremy Fitzhardinge Cc: Yinghai Lu Cc: "Eric W. Biederman" Signed-off-by: H. Peter Anvin

x86, kexec: x86_64: add kexec jump support for x86_64

2009-03-11T01:13:25Z

Impact: New major feature This patch add kexec jump support for x86_64. More information about kexec jump can be found in corresponding x86_32 support patch. Signed-off-by: Huang Ying Signed-off-by: H. Peter Anvin

x86: use _types.h headers in asm where available

2009-02-13T19:35:01Z

In general, the only definitions that assembly files can use are in _types.S headers (where available), so convert them. Signed-off-by: Jeremy Fitzhardinge

x86: use linker to offset symbols by __per_cpu_load

2009-02-09T09:30:30Z

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 Signed-off-by: Brian Gerst Acked-by: Jiri Slaby Signed-off-by: Ingo Molnar

x86, percpu: fix kexec with vmlinux

2009-02-03T05:11:18Z

Impact: fix regression with kexec with vmlinux Split data.init into data.init, percpu, data.init2 sections instead of let data.init wrap percpu secion. Thus kexec loading will be happy, because sections will not overlap. Before the patch we have: Elf file type is EXEC (Executable file) Entry point 0x200000 There are 6 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000200000 0xffffffff80200000 0x0000000000200000 0x0000000000ca6000 0x0000000000ca6000 R E 200000 LOAD 0x0000000000ea6000 0xffffffff80ea6000 0x0000000000ea6000 0x000000000014dfe0 0x000000000014dfe0 RWE 200000 LOAD 0x0000000001000000 0xffffffffff600000 0x0000000000ff4000 0x0000000000000888 0x0000000000000888 RWE 200000 LOAD 0x00000000011f6000 0xffffffff80ff6000 0x0000000000ff6000 0x0000000000073086 0x0000000000a2d938 RWE 200000 LOAD 0x0000000001400000 0x0000000000000000 0x000000000106a000 0x00000000001d2ce0 0x00000000001d2ce0 RWE 200000 NOTE 0x00000000009e2c1c 0xffffffff809e2c1c 0x00000000009e2c1c 0x0000000000000024 0x0000000000000024 4 Section to Segment mapping: Segment Sections... 00 .text .notes __ex_table .rodata __bug_table .pci_fixup .builtin_fw __ksymtab __ksymtab_gpl __ksymtab_strings __init_rodata __param 01 .data .init.rodata .data.cacheline_aligned .data.read_mostly 02 .vsyscall_0 .vsyscall_fn .vsyscall_gtod_data .vsyscall_1 .vsyscall_2 .vgetcpu_mode .jiffies 03 .data.init_task .smp_locks .init.text .init.data .init.setup .initcall.init .con_initcall.init .x86_cpu_dev.init .altinstructions .altinstr_replacement .exit.text .init.ramfs .bss 04 .data.percpu 05 .notes After patch we've got: Elf file type is EXEC (Executable file) Entry point 0x200000 There are 7 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000200000 0xffffffff80200000 0x0000000000200000 0x0000000000ca6000 0x0000000000ca6000 R E 200000 LOAD 0x0000000000ea6000 0xffffffff80ea6000 0x0000000000ea6000 0x000000000014dfe0 0x000000000014dfe0 RWE 200000 LOAD 0x0000000001000000 0xffffffffff600000 0x0000000000ff4000 0x0000000000000888 0x0000000000000888 RWE 200000 LOAD 0x00000000011f6000 0xffffffff80ff6000 0x0000000000ff6000 0x0000000000073086 0x0000000000073086 RWE 200000 LOAD 0x0000000001400000 0x0000000000000000 0x000000000106a000 0x00000000001d2ce0 0x00000000001d2ce0 RWE 200000 LOAD 0x000000000163d000 0xffffffff8123d000 0x000000000123d000 0x0000000000000000 0x00000000007e6938 RWE 200000 NOTE 0x00000000009e2c1c 0xffffffff809e2c1c 0x00000000009e2c1c 0x0000000000000024 0x0000000000000024 4 Section to Segment mapping: Segment Sections... 00 .text .notes __ex_table .rodata __bug_table .pci_fixup .builtin_fw __ksymtab __ksymtab_gpl __ksymtab_strings __init_rodata __param 01 .data .init.rodata .data.cacheline_aligned .data.read_mostly 02 .vsyscall_0 .vsyscall_fn .vsyscall_gtod_data .vsyscall_1 .vsyscall_2 .vgetcpu_mode .jiffies 03 .data.init_task .smp_locks .init.text .init.data .init.setup .initcall.init .con_initcall.init .x86_cpu_dev.init .altinstructions .altinstr_replacement .exit.text .init.ramfs 04 .data.percpu 05 .bss 06 .notes Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar

x86: move stack_canary into irq_stack

2009-01-20T03:29:20Z

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 Signed-off-by: Tejun Heo

x86: convert pda ops to wrappers around x86 percpu accessors

2009-01-16T13:20:22Z

pda is now a percpu variable and there's no reason it can't use plain x86 percpu accessors. Add x86_test_and_clear_bit_percpu() and replace pda op implementations with wrappers around x86 percpu accessors. Signed-off-by: Tejun Heo Signed-off-by: Ingo Molnar