[PATCH v5 14/17] powerpc/8xx: Enable CONFIG_VMAP_STACK
From: Christophe Leroy <hidden>
Date: 2019-12-21 08:32:43
Also in:
linux-mm, lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
This patch enables CONFIG_VMAP_STACK. For that, a few changes are done in head_8xx.S. Signed-off-by: Christophe Leroy <redacted> --- arch/powerpc/kernel/head_8xx.S | 32 ++++++++++++++++++++++++++------ arch/powerpc/platforms/Kconfig.cputype | 1 + 2 files changed, 27 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 225e242ce1c5..477933b36bde 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S@@ -127,7 +127,7 @@ instruction_counter: /* Machine check */ . = 0x200 MachineCheck: - EXCEPTION_PROLOG + EXCEPTION_PROLOG handle_dar_dsisr=1 save_dar_dsisr_on_stack r4, r5, r11 li r6, RPN_PATTERN mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
@@ -140,7 +140,7 @@ MachineCheck: /* Alignment exception */ . = 0x600 Alignment: - EXCEPTION_PROLOG + EXCEPTION_PROLOG handle_dar_dsisr=1 save_dar_dsisr_on_stack r4, r5, r11 li r6, RPN_PATTERN mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
@@ -457,20 +457,26 @@ InstructionTLBError: */ . = 0x1400 DataTLBError: - EXCEPTION_PROLOG_0 + EXCEPTION_PROLOG_0 handle_dar_dsisr=1 mfspr r11, SPRN_DAR cmpwi cr1, r11, RPN_PATTERN beq- cr1, FixupDAR /* must be a buggy dcbX, icbi insn. */ DARFixed:/* Return from dcbx instruction bug workaround */ +#ifdef CONFIG_VMAP_STACK + li r11, RPN_PATTERN + mtspr SPRN_DAR, r11 /* Tag DAR, to be used in DTLB Error */ +#endif EXCEPTION_PROLOG_1 - EXCEPTION_PROLOG_2 + EXCEPTION_PROLOG_2 handle_dar_dsisr=1 get_and_save_dar_dsisr_on_stack r4, r5, r11 andis. r10,r5,DSISR_NOHPTE@h beq+ .Ldtlbie tlbie r4 .Ldtlbie: +#ifndef CONFIG_VMAP_STACK li r10,RPN_PATTERN mtspr SPRN_DAR,r10 /* Tag DAR, to be used in DTLB Error */ +#endif /* 0x300 is DataAccess exception, needed by bad_page_fault() */ EXC_XFER_LITE(0x300, handle_page_fault)
@@ -486,22 +492,29 @@ DARFixed:/* Return from dcbx instruction bug workaround */ rfi #endif +stack_overflow: + vmap_stack_overflow_exception + /* On the MPC8xx, these next four traps are used for development * support of breakpoints and such. Someday I will get around to * using them. */ do_databreakpoint: EXCEPTION_PROLOG_1 - EXCEPTION_PROLOG_2 + EXCEPTION_PROLOG_2 handle_dar_dsisr=1 addi r3,r1,STACK_FRAME_OVERHEAD mfspr r4,SPRN_BAR stw r4,_DAR(r11) +#ifdef CONFIG_VMAP_STACK + lwz r5,_DSISR(r11) +#else mfspr r5,SPRN_DSISR +#endif EXC_XFER_STD(0x1c00, do_break) . = 0x1c00 DataBreakpoint: - EXCEPTION_PROLOG_0 + EXCEPTION_PROLOG_0 handle_dar_dsisr=1 mfspr r11, SPRN_SRR0 cmplwi cr1, r11, (.Ldtlbie - PAGE_OFFSET)@l cmplwi cr7, r11, (.Litlbie - PAGE_OFFSET)@l
@@ -650,7 +663,14 @@ FixupDAR:/* Entry point for dcbx workaround. */ 152: mfdar r11 mtctr r11 /* restore ctr reg from DAR */ +#ifdef CONFIG_VMAP_STACK + mfspr r11, SPRN_SPRG_THREAD + stw r10, DAR(r11) + mfspr r10, SPRN_DSISR + stw r10, DSISR(r11) +#else mtdar r10 /* save fault EA to DAR */ +#endif mfspr r10,SPRN_M_TW b DARFixed /* Go back to normal TLB handling */
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 8d7f9c3dc771..000dd297337c 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype@@ -49,6 +49,7 @@ config PPC_8xx select PPC_HAVE_KUEP select PPC_HAVE_KUAP select PPC_MM_SLICES if HUGETLB_PAGE + select HAVE_ARCH_VMAP_STACK config 40x bool "AMCC 40x"
--
2.13.3