From 51b26ada79b605ed709ddcedbb6012e8f8e0ebed Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 26 Apr 2009 10:12:47 -0700 Subject: x86: unify arch/x86/boot/compressed/vmlinux_*.lds Look at the: diff -u arch/x86/boot/compressed/vmlinux_*.lds output and realize that they're basially exactly the same except for trivial naming differences, and the fact that the 64-bit version has a "pgtable" thing. So unify them. There's some trivial cleanup there (make the output format a Kconfig thing rather than doing #ifdef's for it, and unify both 32-bit and 64-bit BSS end to "_ebss", where 32-bit used to use the traditional "_end"), but other than that it's really very mindless and straigt conversion. For example, I think we should aim to remove "startup_32" vs "startup_64", and just call it "startup", and get rid of one more difference. I didn't do that. Also, notice the comment in the unified vmlinux.lds.S talks about "head_64" and "startup_32" which is an odd and incorrect mix, but that was actually what the old 64-bit only lds file had, so the confusion isn't new, and now that mixing is arguably more accurate thanks to the vmlinux.lds.S file being shared between the two cases ;) [ Impact: cleanup, unification ] Signed-off-by: Linus Torvalds Acked-by: Sam Ravnborg Signed-off-by: Ingo Molnar --- arch/x86/Kconfig | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/x86/Kconfig') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index bc25b9f5e4cd..039c3f04aac5 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -47,6 +47,11 @@ config X86 select HAVE_KERNEL_BZIP2 select HAVE_KERNEL_LZMA +config OUTPUT_FORMAT + string + default "elf32-i386" if X86_32 + default "elf64-x86-64" if X86_64 + config ARCH_DEFCONFIG string default "arch/x86/configs/i386_defconfig" if X86_32 -- cgit v1.2.3 From 845adf7266a7ba6970bf982ffd96abc60d2018ab Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Tue, 5 May 2009 21:20:51 -0700 Subject: x86: add a Kconfig symbol for when relocations are needed We only need to build relocations when we are building a 32-bit relocatable kernel. Rather than unnecessarily complicating the Makefiles, make an explicit Kbuild symbol for this. [ Impact: permits future cleanup ] Signed-off-by: H. Peter Anvin Cc: Sam Ravnborg --- arch/x86/Kconfig | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/x86/Kconfig') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 039c3f04aac5..5aee45356b58 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1513,6 +1513,11 @@ config RELOCATABLE it has been loaded at and the compile time physical address (CONFIG_PHYSICAL_START) is ignored. +# Relocation on x86-32 needs some additional build support +config X86_NEED_RELOCS + def_bool y + depends on X86_32 && RELOCATABLE + config PHYSICAL_ALIGN hex prompt "Alignment value to which kernel should be aligned" if X86_32 -- cgit v1.2.3 From ceefccc93932b920a8ec6f35f596db05202a12fe Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 11 May 2009 16:12:16 -0700 Subject: x86: default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN to 16 MB Default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN each to 16 MB, so that both non-relocatable and relocatable kernels are loaded at 16 MB by a non-relocating bootloader. This is somewhat hacky, but it appears to be the only way to do this that does not break some some set of existing bootloaders. We want to avoid the bottom 16 MB because of large page breakup, memory holes, and ZONE_DMA. Embedded systems may need to reduce this, or update their bootloaders to be aware of the new min_alignment field. [ Impact: performance improvement, avoids problems on some systems ] Signed-off-by: H. Peter Anvin --- arch/x86/Kconfig | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) (limited to 'arch/x86/Kconfig') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 5aee45356b58..50fbb47f5295 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1455,9 +1455,7 @@ config KEXEC_JUMP config PHYSICAL_START hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) - default "0x1000000" if X86_NUMAQ - default "0x200000" if X86_64 - default "0x100000" + default "0x1000000" ---help--- This gives the physical address where the kernel is loaded. @@ -1476,15 +1474,15 @@ config PHYSICAL_START to be specifically compiled to run from a specific memory area (normally a reserved region) and this option comes handy. - So if you are using bzImage for capturing the crash dump, leave - the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. - Otherwise if you plan to use vmlinux for capturing the crash dump - change this value to start of the reserved region (Typically 16MB - 0x1000000). In other words, it can be set based on the "X" value as - specified in the "crashkernel=YM@XM" command line boot parameter - passed to the panic-ed kernel. Typically this parameter is set as - crashkernel=64M@16M. Please take a look at - Documentation/kdump/kdump.txt for more details about crash dumps. + So if you are using bzImage for capturing the crash dump, + leave the value here unchanged to 0x1000000 and set + CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux + for capturing the crash dump change this value to start of + the reserved region. In other words, it can be set based on + the "X" value as specified in the "crashkernel=YM@XM" + command line boot parameter passed to the panic-ed + kernel. Please take a look at Documentation/kdump/kdump.txt + for more details about crash dumps. Usage of bzImage for capturing the crash dump is recommended as one does not have to build two kernels. Same kernel can be used @@ -1521,9 +1519,8 @@ config X86_NEED_RELOCS config PHYSICAL_ALIGN hex prompt "Alignment value to which kernel should be aligned" if X86_32 - default "0x100000" if X86_32 - default "0x200000" if X86_64 - range 0x2000 0x400000 + default "0x1000000" + range 0x2000 0x1000000 ---help--- This value puts the alignment restrictions on physical address where kernel is loaded and run from. Kernel is compiled for an -- cgit v1.2.3 From 26717808f93a27c22d4853c4fb17fa225f4ccc68 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Thu, 7 May 2009 14:19:34 -0700 Subject: x86: make CONFIG_RELOCATABLE the default Remove the EXPERIMENTAL tag from CONFIG_RELOCATABLE and make it the default. Relocatable kernels have been used for a while now, and should now have identical semantics to non-relocatable kernels when loaded by a non-relocating bootloader. Signed-off-by: H. Peter Anvin --- arch/x86/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/x86/Kconfig') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 50fbb47f5295..3e0f80a764a7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1495,8 +1495,8 @@ config PHYSICAL_START Don't change this unless you know what you are doing. config RELOCATABLE - bool "Build a relocatable kernel (EXPERIMENTAL)" - depends on EXPERIMENTAL + bool "Build a relocatable kernel" + default y ---help--- This builds a kernel image that retains relocation information so it can be loaded someplace besides the default 1MB. -- cgit v1.2.3