From 0eb1bfa5e7051939e76be07de1e872e467246c30 Mon Sep 17 00:00:00 2001 From: Nathan Whitehorn Date: Mon, 9 Feb 2015 02:12:38 +0000 Subject: [PATCH] Simplify trapcode setup by placing a copy of the generic trap handler at every possible trap address by default. This also makes sure the kernel notices (and panics at) traps from newer CPUs that the kernel was not expecting rather than executing gibberish memory. --- sys/powerpc/aim/machdep.c | 67 +++++++++++++++++++-------------------- 1 file changed, 32 insertions(+), 35 deletions(-) diff --git a/sys/powerpc/aim/machdep.c b/sys/powerpc/aim/machdep.c index 020c07ab48f1..2980b0997783 100644 --- a/sys/powerpc/aim/machdep.c +++ b/sys/powerpc/aim/machdep.c @@ -256,6 +256,7 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry, void *mdp) vm_offset_t startkernel, endkernel; void *generictrap; size_t trap_offset, trapsize; + vm_offset_t trap; void *kmdp; char *env; register_t msr, scratch; @@ -480,20 +481,6 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry, void *mdp) bcopy(&rfid_patch,&rfi_patch2,4); #endif - /* - * Copy a code snippet to restore 32-bit bridge mode - * to the top of every non-generic trap handler - */ - - trap_offset += (size_t)&restorebridgesize; - bcopy(&restorebridge, (void *)EXC_RST, trap_offset); - bcopy(&restorebridge, (void *)EXC_DSI, trap_offset); - bcopy(&restorebridge, (void *)EXC_ALI, trap_offset); - bcopy(&restorebridge, (void *)EXC_PGM, trap_offset); - bcopy(&restorebridge, (void *)EXC_MCHK, trap_offset); - bcopy(&restorebridge, (void *)EXC_TRC, trap_offset); - bcopy(&restorebridge, (void *)EXC_BPT, trap_offset); - /* * Set the common trap entry point to the one that * knows to restore 32-bit operation on execution. @@ -507,14 +494,35 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry, void *mdp) #else /* powerpc64 */ cpu_features |= PPC_FEATURE_64; generictrap = &trapcode; - - /* Set TOC base so that the interrupt code can get at it */ - *((void **)TRAP_GENTRAP) = &trapcode2; - *((register_t *)TRAP_TOCBASE) = toc; #endif trapsize = (size_t)&trapcodeend - (size_t)&trapcode; + /* + * Copy generic handler into every possible trap. Special cases will get + * different ones in a minute. + */ + for (trap = EXC_RST; trap < EXC_LAST; trap += 0x20) + bcopy(generictrap, (void *)trap, trapsize); + + #ifndef __powerpc64__ + if (cpu_features & PPC_FEATURE_64) { + /* + * Copy a code snippet to restore 32-bit bridge mode + * to the top of every non-generic trap handler + */ + + trap_offset += (size_t)&restorebridgesize; + bcopy(&restorebridge, (void *)EXC_RST, trap_offset); + bcopy(&restorebridge, (void *)EXC_DSI, trap_offset); + bcopy(&restorebridge, (void *)EXC_ALI, trap_offset); + bcopy(&restorebridge, (void *)EXC_PGM, trap_offset); + bcopy(&restorebridge, (void *)EXC_MCHK, trap_offset); + bcopy(&restorebridge, (void *)EXC_TRC, trap_offset); + bcopy(&restorebridge, (void *)EXC_BPT, trap_offset); + } + #endif + bcopy(&rstcode, (void *)(EXC_RST + trap_offset), (size_t)&rstcodeend - (size_t)&rstcode); @@ -527,31 +535,20 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry, void *mdp) (size_t)&dblow); bcopy(&dblow, (void *)(EXC_BPT + trap_offset), (size_t)&dbend - (size_t)&dblow); -#else - bcopy(generictrap, (void *)EXC_MCHK, trapsize); - bcopy(generictrap, (void *)EXC_PGM, trapsize); - bcopy(generictrap, (void *)EXC_TRC, trapsize); - bcopy(generictrap, (void *)EXC_BPT, trapsize); #endif bcopy(&alitrap, (void *)(EXC_ALI + trap_offset), (size_t)&aliend - (size_t)&alitrap); bcopy(&dsitrap, (void *)(EXC_DSI + trap_offset), (size_t)&dsiend - (size_t)&dsitrap); - bcopy(generictrap, (void *)EXC_ISI, trapsize); + #ifdef __powerpc64__ + /* Set TOC base so that the interrupt code can get at it */ + *((void **)TRAP_GENTRAP) = &trapcode2; + *((register_t *)TRAP_TOCBASE) = toc; + bcopy(&slbtrap, (void *)EXC_DSE,(size_t)&slbtrapend - (size_t)&slbtrap); bcopy(&slbtrap, (void *)EXC_ISE,(size_t)&slbtrapend - (size_t)&slbtrap); - #endif - bcopy(generictrap, (void *)EXC_EXI, trapsize); - bcopy(generictrap, (void *)EXC_FPU, trapsize); - bcopy(generictrap, (void *)EXC_DECR, trapsize); - bcopy(generictrap, (void *)EXC_SC, trapsize); - bcopy(generictrap, (void *)EXC_FPA, trapsize); - bcopy(generictrap, (void *)EXC_VEC, trapsize); - bcopy(generictrap, (void *)EXC_PERF, trapsize); - bcopy(generictrap, (void *)EXC_VECAST_G4, trapsize); - bcopy(generictrap, (void *)EXC_VECAST_G5, trapsize); - #ifndef __powerpc64__ + #else /* G2-specific TLB miss helper handlers */ bcopy(&imisstrap, (void *)EXC_IMISS, (size_t)&imisssize); bcopy(&dlmisstrap, (void *)EXC_DLMISS, (size_t)&dlmisssize);