From 98bf2d3f4970179c702ef64db658e0553bc6ef3a Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 22 Dec 2020 07:11:18 +0000 Subject: [PATCH 1/2] powerpc/32s: Fix RTAS machine check with VMAP stack When we have VMAP stack, exception prolog 1 sets r1, not r11. When it is not an RTAS machine check, don't trash r1 because it is needed by prolog 1. Fixes: da7bb43ab9da ("powerpc/32: Fix vmap stack - Properly set r1 before activating MMU") Fixes: d2e006036082 ("powerpc/32: Use SPRN_SPRG_SCRATCH2 in exception prologs") Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Christophe Leroy [mpe: Squash in fixup for RTAS machine check from Christophe] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/bc77d61d1c18940e456a2dee464f1e2eda65a3f0.1608621048.git.christophe.leroy@csgroup.eu --- arch/powerpc/kernel/head_book3s_32.S | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index 349bf3f0c3af..858fbc8b19f3 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -260,10 +260,19 @@ __secondary_hold_acknowledge: MachineCheck: EXCEPTION_PROLOG_0 #ifdef CONFIG_PPC_CHRP +#ifdef CONFIG_VMAP_STACK + mtspr SPRN_SPRG_SCRATCH2,r1 + mfspr r1, SPRN_SPRG_THREAD + lwz r1, RTAS_SP(r1) + cmpwi cr1, r1, 0 + bne cr1, 7f + mfspr r1, SPRN_SPRG_SCRATCH2 +#else mfspr r11, SPRN_SPRG_THREAD lwz r11, RTAS_SP(r11) cmpwi cr1, r11, 0 bne cr1, 7f +#endif #endif /* CONFIG_PPC_CHRP */ EXCEPTION_PROLOG_1 for_rtas=1 7: EXCEPTION_PROLOG_2 From 3ce47d95b7346dcafd9bed3556a8d072cb2b8571 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Mon, 4 Jan 2021 13:59:53 -0700 Subject: [PATCH 2/2] powerpc: Handle .text.{hot,unlikely}.* in linker script Commit eff8728fe698 ("vmlinux.lds.h: Add PGO and AutoFDO input sections") added ".text.unlikely.*" and ".text.hot.*" due to an LLVM change [1]. After another LLVM change [2], these sections are seen in some PowerPC builds, where there is a orphan section warning then build failure: $ make -skj"$(nproc)" \ ARCH=powerpc CROSS_COMPILE=powerpc64le-linux-gnu- LLVM=1 O=out \ distclean powernv_defconfig zImage.epapr ld.lld: warning: kernel/built-in.a(panic.o):(.text.unlikely.) is being placed in '.text.unlikely.' ... ld.lld: warning: address (0xc000000000009314) of section .text is not a multiple of alignment (256) ... ERROR: start_text address is c000000000009400, should be c000000000008000 ERROR: try to enable LD_HEAD_STUB_CATCH config option ERROR: see comments in arch/powerpc/tools/head_check.sh ... Explicitly handle these sections like in the main linker script so there is no more build failure. [1]: https://reviews.llvm.org/D79600 [2]: https://reviews.llvm.org/D92493 Fixes: 83a092cf95f2 ("powerpc: Link warning for orphan sections") Cc: stable@vger.kernel.org Signed-off-by: Nathan Chancellor Signed-off-by: Michael Ellerman Link: https://github.com/ClangBuiltLinux/linux/issues/1218 Link: https://lore.kernel.org/r/20210104205952.1399409-1-natechancellor@gmail.com --- arch/powerpc/kernel/vmlinux.lds.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 0318ba436f34..8e0b1298bf19 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -85,7 +85,7 @@ SECTIONS ALIGN_FUNCTION(); #endif /* careful! __ftr_alt_* sections need to be close to .text */ - *(.text.hot TEXT_MAIN .text.fixup .text.unlikely .fixup __ftr_alt_* .ref.text); + *(.text.hot .text.hot.* TEXT_MAIN .text.fixup .text.unlikely .text.unlikely.* .fixup __ftr_alt_* .ref.text); #ifdef CONFIG_PPC64 *(.tramp.ftrace.text); #endif