diff options
| author |   Nicholas Piggin <npiggin@gmail.com> | 2021-06-30 17:46:16 +1000 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2021-06-30 22:21:20 +1000 |
| commit | 325678fd052259e7c05ef29060a73c705ea90432 (patch) | |
| tree | 4af33e651e345d979c3cdca9af3f9bccd7e10f38 /arch/powerpc/include/asm | |
| parent | powerpc/64e: remove implicit soft-masking and interrupt exit restart logic (diff) | |
| download | linux-dev-325678fd052259e7c05ef29060a73c705ea90432.tar.xz linux-dev-325678fd052259e7c05ef29060a73c705ea90432.zip | |
powerpc/64s: add a table of implicit soft-masked addresses
Commit 9d1988ca87dd ("powerpc/64: treat low kernel text as irqs
soft-masked") ends up catching too much code, including ret_from_fork,
and parts of interrupt and syscall return that do not expect to be
interrupts to be soft-masked. If an interrupt gets marked pending,
and then the code proceeds out of the implicit soft-masked region it
will fail to deal with the pending interrupt.
Fix this by adding a new table of addresses which explicitly marks
the regions of code that are soft masked. This table is only checked
for interrupts that below __end_soft_masked, so most kernel interrupts
will not have the overhead of the table search.
Fixes: 9d1988ca87dd ("powerpc/64: treat low kernel text as irqs soft-masked")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210630074621.2109197-5-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/include/asm')
| -rw-r--r-- | arch/powerpc/include/asm/interrupt.h | 3 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/ppc_asm.h | 7 |
2 files changed, 9 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index f13c93b033c7..d7df247a149c 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -75,6 +75,7 @@ #ifdef CONFIG_PPC_BOOK3S_64 extern char __end_soft_masked[]; +bool search_kernel_soft_mask_table(unsigned long addr); unsigned long search_kernel_restart_table(unsigned long addr); DECLARE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant); @@ -87,7 +88,7 @@ static inline bool is_implicit_soft_masked(struct pt_regs *regs) if (regs->nip >= (unsigned long)__end_soft_masked) return false; - return true; + return search_kernel_soft_mask_table(regs->nip); } static inline void srr_regs_clobbered(void) diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h index c9c2c36c1f8f..116c1519728a 100644 --- a/arch/powerpc/include/asm/ppc_asm.h +++ b/arch/powerpc/include/asm/ppc_asm.h @@ -762,6 +762,13 @@ 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 SOFT_MASK_TABLE(_start, _end) \ + stringify_in_c(.section __soft_mask_table,"a";)\ + stringify_in_c(.balign 8;) \ + stringify_in_c(.llong (_start);) \ + stringify_in_c(.llong (_end);) \ + stringify_in_c(.previous) + #define RESTART_TABLE(_start, _end, _target) \ stringify_in_c(.section __restart_table,"a";)\ stringify_in_c(.balign 8;) \ |