Changes in Makefile

afedc312 - riscv: Do not use fortify in early code

Wed, 09 Oct 2024 07:27:49 +0000

riscv: Do not use fortify in early codeEarly code designates the code executed when the MMU is not yet enabled,and this comes with some limitations (seeDocumentation/arch/riscv/boot.rst, section "Pre-MMU execution").FORTIFY_SOURCE must be disabled then since it can trigger kernel panicsas reported in [1].Reported-by: Jason Montleon Closes: https://lore.kernel.org/linux-riscv/CAJD_bPJes4QhmXY5f63GHV9B9HFkSCoaZjk-qCT2NGS7Q9HODg@mail.gmail.com/ [1]Fixes: a35707c3d850 ("riscv: add memory-type errata for T-Head")Fixes: 26e7aacb83df ("riscv: Allow to downgrade paging mode from the command line")Cc: stable@vger.kernel.orgSigned-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20241009072749.45006-1-alexghiti@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

945302df - RISC-V: Use Zkr to seed KASLR base address

Tue, 09 Jul 2024 17:39:37 +0000

RISC-V: Use Zkr to seed KASLR base addressParse the device tree for Zkr in the isa string.If Zkr is present, use it to seed the kernel base address.On an ACPI system, as of this commit, there is no easy way to check ifZkr is present. Blindly running the instruction isn't an option as;we have to be able to trust the firmware.Signed-off-by: Jesse Taube Reviewed-by: Charlie Jenkins Reviewed-by: Alexandre Ghiti Tested-by: Zong Li Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20240709173937.510084-5-jesse@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

14c3ec67 - RISC-V: pi: Force hidden visibility for all symbol references

Tue, 09 Jul 2024 17:39:34 +0000

RISC-V: pi: Force hidden visibility for all symbol referencesEliminate all GOT entries in the .pi section, by forcing hiddenvisibility for all symbol references, which informs the compiler thatsuch references will be resolved at link time without the need forallocating GOT entries.Include linux/hidden.h in Makefile, like arm64, for thehidden visibility attribute.Signed-off-by: Jesse Taube Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20240709173937.510084-2-jesse@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

7f7f6f7a - Makefile: remove redundant tool coverage variables

Mon, 06 May 2024 13:35:43 +0000

Makefile: remove redundant tool coverage variablesNow Kbuild provides reasonable defaults for objtool, sanitizers, andprofilers.Remove redundant variables.Note:This commit changes the coverage for some objects: - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV - include arch/sparc/vdso/vdso-image-*.o into UBSAN - include arch/sparc/vdso/vma.o into UBSAN - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vma.o into GCOV, KCOV - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOVI believe these are positive effects because all of them are kernelspace objects.Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook Tested-by: Roberto Sassu List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

021d2342 - RISC-V: build: Allow LTO to be selected

Tue, 17 Oct 2023 22:21:04 +0000

RISC-V: build: Allow LTO to be selectedAllow LTO to be selected for RISC-V, only when LLD >= 14, since there isan issue [1] in prior LLD versions that prevents LLD to generate propermachine code for RISC-V when writing `nop`s.To avoid boot failures in QEMU [2], '-mattr=+c' and '-mattr=+relax'need to be passed via '-mllvm' to ld.lld, as there appears to be anissue with LLVM's target-features and LTO [3], which can result inincorrect relocations to branch targets [4]. Once this is fixed in LLVM,it can be made conditional on affected ld.lld versions.Disable LTO for arch/riscv/kernel/pi, as llvm-objcopy expects an ELFobject file when manipulating the files in that subfolder, rather thanLLVM bitcode.[1] https://github.com/llvm/llvm-project/issues/50505, resolved by LLVM commit e63455d5e0e5 ("[MC] Use local MCSubtargetInfo in writeNops")[2] https://github.com/ClangBuiltLinux/linux/issues/1942[3] https://github.com/llvm/llvm-project/issues/59350[4] https://github.com/llvm/llvm-project/issues/65090Tested-by: Wende Tan Signed-off-by: Wende Tan Co-developed-by: Nathan Chancellor Signed-off-by: Nathan Chancellor Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20231017-riscv-lto-v4-1-e7810b24e805@kernel.orgSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

84fe419d - riscv: Introduce virtual kernel mapping KASLR

Sat, 22 Jul 2023 12:38:46 +0000

riscv: Introduce virtual kernel mapping KASLRKASLR implementation relies on a relocatable kernel so that we can movethe kernel mapping.The seed needed to virtually move the kernel is taken from the device tree,so we rely on the bootloader to provide a correct seed. Zkr could be usedunconditionnally instead if implemented, but that's for another patch.Signed-off-by: Alexandre Ghiti Tested-by: Conor Dooley Tested-by: Song Shuai Reviewed-by: Sami Tolvanen Tested-by: Sami Tolvanen Link: https://lore.kernel.org/r/20230722123850.634544-2-alexghiti@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

3b90b09a - riscv: Fix orphan section warnings caused by kernel/pi

Thu, 04 May 2023 12:07:59 +0000

riscv: Fix orphan section warnings caused by kernel/pikernel/pi gives rise to a lot of new sections that end up orphans: thefirst attempt to fix that tried to enumerate them all in the linkerscript, but kernel test robot with a random config keeps finding more ofthem.So prefix all those sections with .init.pi instead of only .init inorder to be able to easily catch them all in the linker script.Reported-by: kernel test robot Link: https://lore.kernel.org/oe-kbuild-all/202304301606.Cgp113Ha-lkp@intel.com/Fixes: 26e7aacb83df ("riscv: Allow to downgrade paging mode from the command line")Signed-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20230504120759.18730-1-alexghiti@rivosinc.comCc: stable@vger.kernel.orgSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile

26e7aacb - riscv: Allow to downgrade paging mode from the command line

Mon, 24 Apr 2023 09:23:13 +0000

riscv: Allow to downgrade paging mode from the command lineAdd 2 early command line parameters that allow to downgrade satp mode(using the same naming as x86):- "no5lvl": use a 4-level page table (down from sv57 to sv48)- "no4lvl": use a 3-level page table (down from sv57/sv48 to sv39)Note that going through the device tree to get the kernel command lineworks with ACPI too since the efi stub creates a device tree anyway withthe command line.In KASAN kernels, we can't use the libfdt that early in the boot processsince we are not ready to execute instrumented functions. So instead ofusing the "generic" libfdt, we compile our own versions of those functionsthat are not instrumented and that are prefixed so that they do notconflict with the generic ones. We also need the non-instrumented versionsof the string functions and the prefixed versions of memcpy/memmove.This is largely inspired by commit aacd149b6238 ("arm64: head: avoidrelocating the kernel twice for KASLR") from which I removed compilationflags that were not relevant to RISC-V at the moment (LTO, SCS). Alsonote that we have to link with -z norelro to avoid ld.lld to throw awarning with the new .got sections, like in commit 311bea3cb9ee ("arm64:link with -z norelro for LLD or aarch64-elf").Signed-off-by: Alexandre Ghiti Tested-by: Björn Töpel Reviewed-by: Björn Töpel Link: https://lore.kernel.org/r/20230424092313.178699-2-alexghiti@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/kernel/pi/Makefile