diff --git a/arch/s390/include/asm/asm-extable.h b/arch/s390/include/asm/asm-extable.h index 61484a5f1209..fb62df5e16a2 100644 --- a/arch/s390/include/asm/asm-extable.h +++ b/arch/s390/include/asm/asm-extable.h @@ -8,6 +8,7 @@ #define EX_TYPE_NONE 0 #define EX_TYPE_FIXUP 1 #define EX_TYPE_BPF 2 +#define EX_TYPE_UACCESS 3 #define __EX_TABLE(_section, _fault, _target, _type) \ stringify_in_c(.section _section,"a";) \ @@ -18,9 +19,35 @@ stringify_in_c(.short 0;) \ stringify_in_c(.previous) +#define __EX_TABLE_UA(_section, _fault, _target, _type, _reg) \ + stringify_in_c(.section _section,"a";) \ + stringify_in_c(.align 4;) \ + stringify_in_c(.long (_fault) - .;) \ + stringify_in_c(.long (_target) - .;) \ + stringify_in_c(.short (_type);) \ + stringify_in_c(.macro extable_reg reg;) \ + stringify_in_c(.set found, 0;) \ + stringify_in_c(.set regnr, 0;) \ + stringify_in_c(.irp rs,r0,r1,r2,r3,r4,r5,r6,r7,r8,r9,r10,r11,r12,r13,r14,r15;) \ + stringify_in_c(.ifc "\reg", "%%\rs";) \ + stringify_in_c(.set found, 1;) \ + stringify_in_c(.short regnr;) \ + stringify_in_c(.endif;) \ + stringify_in_c(.set regnr, regnr+1;) \ + stringify_in_c(.endr;) \ + stringify_in_c(.ifne (found != 1);) \ + stringify_in_c(.error "extable_reg: bad register argument";) \ + stringify_in_c(.endif;) \ + stringify_in_c(.endm;) \ + stringify_in_c(extable_reg _reg;) \ + stringify_in_c(.purgem extable_reg;) \ + stringify_in_c(.previous) + #define EX_TABLE(_fault, _target) \ __EX_TABLE(__ex_table, _fault, _target, EX_TYPE_FIXUP) #define EX_TABLE_AMODE31(_fault, _target) \ __EX_TABLE(.amode31.ex_table, _fault, _target, EX_TYPE_FIXUP) +#define EX_TABLE_UA(_fault, _target, _reg) \ + __EX_TABLE_UA(__ex_table, _fault, _target, EX_TYPE_UACCESS, _reg) #endif /* __ASM_EXTABLE_H */ diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index 2c029ee89b7c..44b18800721a 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -81,14 +81,10 @@ union oac { "0: mvcos %[_to],%[_from],%[_size]\n" \ "1: xr %[rc],%[rc]\n" \ "2:\n" \ - ".pushsection .fixup, \"ax\"\n" \ - "3: lhi %[rc],%[retval]\n" \ - " jg 2b\n" \ - ".popsection\n" \ - EX_TABLE(0b,3b) EX_TABLE(1b,3b) \ + EX_TABLE_UA(0b,2b,%[rc]) EX_TABLE_UA(1b,2b,%[rc]) \ : [rc] "=&d" (__rc), [_to] "+Q" (*(to)) \ : [_size] "d" (size), [_from] "Q" (*(from)), \ - [retval] "K" (-EFAULT), [spec] "d" (oac_spec.val) \ + [spec] "d" (oac_spec.val) \ : "cc", "0"); \ __rc; \ }) @@ -295,13 +291,9 @@ int __noreturn __put_kernel_bad(void); "0: " insn " %2,%1\n" \ "1: xr %0,%0\n" \ "2:\n" \ - ".pushsection .fixup, \"ax\"\n" \ - "3: lhi %0,%3\n" \ - " jg 2b\n" \ - ".popsection\n" \ - EX_TABLE(0b,3b) EX_TABLE(1b,3b) \ + EX_TABLE_UA(0b,2b,%0) EX_TABLE_UA(1b,2b,%0) \ : "=d" (__rc), "+Q" (*(to)) \ - : "d" (val), "K" (-EFAULT) \ + : "d" (val) \ : "cc"); \ __rc; \ }) @@ -342,13 +334,9 @@ int __noreturn __get_kernel_bad(void); "0: " insn " %1,%2\n" \ "1: xr %0,%0\n" \ "2:\n" \ - ".pushsection .fixup, \"ax\"\n" \ - "3: lhi %0,%3\n" \ - " jg 2b\n" \ - ".popsection\n" \ - EX_TABLE(0b,3b) EX_TABLE(1b,3b) \ + EX_TABLE_UA(0b,2b,%0) EX_TABLE_UA(1b,2b,%0) \ : "=d" (__rc), "+d" (val) \ - : "Q" (*(from)), "K" (-EFAULT) \ + : "Q" (*(from)) \ : "cc"); \ __rc; \ }) diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c index ac6b736ac883..8ac8ad2474a0 100644 --- a/arch/s390/mm/extable.c +++ b/arch/s390/mm/extable.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include #include #include #include @@ -23,6 +24,13 @@ static bool ex_handler_fixup(const struct exception_table_entry *ex, struct pt_r return true; } +static bool ex_handler_uaccess(const struct exception_table_entry *ex, struct pt_regs *regs) +{ + regs->gprs[ex->data] = -EFAULT; + regs->psw.addr = extable_fixup(ex); + return true; +} + bool fixup_exception(struct pt_regs *regs) { const struct exception_table_entry *ex; @@ -35,6 +43,8 @@ bool fixup_exception(struct pt_regs *regs) return ex_handler_fixup(ex, regs); case EX_TYPE_BPF: return ex_handler_bpf(ex, regs); + case EX_TYPE_UACCESS: + return ex_handler_uaccess(ex, regs); } panic("invalid exception table entry"); }