From f23699c93becd746295aaa506537882a46a62219 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 18 Jun 2021 01:51:08 +1000 Subject: powerpc/64: allow alternate return locations for soft-masked interrupts The exception table fixup adjusts a failed page fault's interrupt return location if it was taken at an address specified in the exception table, to a corresponding fixup handler address. Introduce a variation of that idea which adds a fixup table for NMIs and soft-masked asynchronous interrupts. This will be used to protect certain critical sections that are sensitive to being clobbered by interrupts coming in (due to using the same SPRs and/or irq soft-mask state). Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210617155116.2167984-10-npiggin@gmail.com --- arch/powerpc/include/asm/ppc_asm.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/powerpc/include/asm/ppc_asm.h') diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h index d6739d700f0a..c9c2c36c1f8f 100644 --- a/arch/powerpc/include/asm/ppc_asm.h +++ b/arch/powerpc/include/asm/ppc_asm.h @@ -762,6 +762,14 @@ END_FTR_SECTION_NESTED(CPU_FTR_CELL_TB_BUG, CPU_FTR_CELL_TB_BUG, 96) stringify_in_c(.long (_target) - . ;) \ stringify_in_c(.previous) +#define RESTART_TABLE(_start, _end, _target) \ + stringify_in_c(.section __restart_table,"a";)\ + stringify_in_c(.balign 8;) \ + stringify_in_c(.llong (_start);) \ + stringify_in_c(.llong (_end);) \ + stringify_in_c(.llong (_target);) \ + stringify_in_c(.previous) + #ifdef CONFIG_PPC_FSL_BOOK3E #define BTB_FLUSH(reg) \ lis reg,BUCSR_INIT@h; \ -- cgit v1.2.3-59-g8ed1b