Hi, On Wed, Apr 24, 2024 at 11:26:59AM -0700, Nathan Chancellor wrote: > On Wed, Apr 24, 2024 at 05:53:12PM +0200, Ard Biesheuvel wrote: > > From: Ard Biesheuvel <ardb@xxxxxxxxxx> > > > > The x86 purgatory, which does little more than verify a SHA-256 hash of > > the loaded segments, currently uses three different stacks: > > - one in .bss that is used to call the purgatory C code > > - one in .rodata that is only used to switch to an updated code segment > > descriptor in the GDT > > - one in .data, which allows it to be prepopulated from the kexec loader > > in theory, but this is not actually being taken advantage of. > > > > Simplify this, by dropping the latter two stacks, as well as the loader > > logic that programs RSP. > > > > Both the stacks in .bss and .data are 4k aligned, but 16 byte alignment > > is more than sufficient. > > > > Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > --- > > arch/x86/include/asm/kexec.h | 1 - > > arch/x86/kernel/kexec-bzimage64.c | 8 -------- > > arch/x86/purgatory/entry64.S | 8 -------- > > arch/x86/purgatory/setup-x86_64.S | 2 +- > > arch/x86/purgatory/stack.S | 18 ------------------ > > This needs a small fix up to build. > > make[6]: *** No rule to make target 'arch/x86/purgatory/stack.o', needed by 'arch/x86/purgatory/purgatory.ro'. > I was trying to reproduce this build failure, but to no avail. I am curious what your build target / build command was. It is clear that stack.S has been removed so your change makes sense, I don't doubt that -- I just cannot get that specific error message you encountered (what is a .ro file supposed to be, anyway?). > diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile > index acc09799af2a..2b6b2fb033d6 100644 > --- a/arch/x86/purgatory/Makefile > +++ b/arch/x86/purgatory/Makefile > @@ -1,7 +1,7 @@ > # SPDX-License-Identifier: GPL-2.0 > OBJECT_FILES_NON_STANDARD := y > > -purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o > +purgatory-y := purgatory.o setup-x86_$(BITS).o sha256.o entry64.o string.o > > targets += $(purgatory-y) > PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) Thanks Justin _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
