s390/entry: Make pgm_check_handler() ready for lowcore relocation

In preparation of having lowcore at different address than zero,
add the base register to all lowcore accesses in pgm_check_handler().

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index 52c90b65a2b84f14561ae04dba1c123afcfa6901..183ac29afaf8214d6b19116799fc1b39ebda95dc 100644 (file)
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -244,5 +244,11 @@ static inline void set_prefix(__u32 address)
                ALT_LOWCORE
 .endm
 
+.macro STMG_LC start, end, savearea
+       ALTERNATIVE "stmg       \start, \end, \savearea",                               \
+               __stringify(stmg        \start, \end, LOWCORE_ALT_ADDRESS + \savearea), \
+               ALT_LOWCORE
+.endm
+
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_S390_LOWCORE_H */

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 1d12f3c29a436a617e319ecb3fdb47b41cef71a7..5f63f3fbb34c36a4109b8cd7e9d603305676cadf 100644 (file)
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -40,8 +40,11 @@ _LPP_OFFSET  = __LC_LPP
        ALTERNATIVE "nop", ".insn s,0xb2000000,\address", ALT_FACILITY(193)
        .endm
 
-       .macro LPSWEY address,lpswe
-       ALTERNATIVE "b \lpswe; nopr", ".insn siy,0xeb0000000071,\address,0", ALT_FACILITY(193)
+       .macro LPSWEY address, lpswe
+       ALTERNATIVE_2 "b \lpswe;nopr", \
+               ".insn siy,0xeb0000000071,\address,0", ALT_FACILITY_EARLY(193),         \
+               __stringify(.insn siy,0xeb0000000071,LOWCORE_ALT_ADDRESS+\address,0),   \
+               ALT_LOWCORE
        .endm
 
        .macro MBEAR reg, lowcore
@@ -317,39 +320,40 @@ SYM_CODE_END(ret_from_fork)
  */
 
 SYM_CODE_START(pgm_check_handler)
-       stpt    __LC_SYS_ENTER_TIMER
+       STMG_LC %r8,%r15,__LC_SAVE_AREA_SYNC
+       GET_LC  %r13
+       stpt    __LC_SYS_ENTER_TIMER(%r13)
        BPOFF
-       stmg    %r8,%r15,__LC_SAVE_AREA_SYNC
        lgr     %r10,%r15
-       lmg     %r8,%r9,__LC_PGM_OLD_PSW
+       lmg     %r8,%r9,__LC_PGM_OLD_PSW(%r13)
        tmhh    %r8,0x0001              # coming from user space?
        jno     .Lpgm_skip_asce
-       lctlg   %c1,%c1,__LC_KERNEL_ASCE
+       lctlg   %c1,%c1,__LC_KERNEL_ASCE(%r13)
        j       3f                      # -> fault in user space
 .Lpgm_skip_asce:
 1:     tmhh    %r8,0x4000              # PER bit set in old PSW ?
        jnz     2f                      # -> enabled, can't be a double fault
-       tm      __LC_PGM_ILC+3,0x80     # check for per exception
+       tm      __LC_PGM_ILC+3(%r13),0x80       # check for per exception
        jnz     .Lpgm_svcper            # -> single stepped svc
-2:     CHECK_STACK __LC_SAVE_AREA_SYNC,%r0
+2:     CHECK_STACK __LC_SAVE_AREA_SYNC,%r13
        aghi    %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
        # CHECK_VMAP_STACK branches to stack_overflow or 4f
-       CHECK_VMAP_STACK __LC_SAVE_AREA_SYNC,%r0,4f
-3:     lg      %r15,__LC_KERNEL_STACK
+       CHECK_VMAP_STACK __LC_SAVE_AREA_SYNC,%r13,4f
+3:     lg      %r15,__LC_KERNEL_STACK(%r13)
 4:     la      %r11,STACK_FRAME_OVERHEAD(%r15)
        xc      __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
        xc      __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
        stmg    %r0,%r7,__PT_R0(%r11)
-       mvc     __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
-       mvc     __PT_LAST_BREAK(8,%r11),__LC_PGM_LAST_BREAK
+       mvc     __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC(%r13)
+       mvc     __PT_LAST_BREAK(8,%r11),__LC_PGM_LAST_BREAK(%r13)
        stctg   %c1,%c1,__PT_CR1(%r11)
 #if IS_ENABLED(CONFIG_KVM)
-       ltg     %r12,__LC_GMAP
+       ltg     %r12,__LC_GMAP(%r13)
        jz      5f
        clc     __GMAP_ASCE(8,%r12), __PT_CR1(%r11)
        jne     5f
        BPENTER __SF_SIE_FLAGS(%r10),_TIF_ISOLATE_BP_GUEST
-       SIEEXIT __SF_SIE_CONTROL(%r10),%r0
+       SIEEXIT __SF_SIE_CONTROL(%r10),%r13
 #endif
 5:     stmg    %r8,%r9,__PT_PSW(%r11)
        # clear user controlled registers to prevent speculative use
@@ -365,11 +369,11 @@ SYM_CODE_START(pgm_check_handler)
        tmhh    %r8,0x0001              # returning to user space?
        jno     .Lpgm_exit_kernel
        STACKLEAK_ERASE
-       lctlg   %c1,%c1,__LC_USER_ASCE
+       lctlg   %c1,%c1,__LC_USER_ASCE(%r13)
        BPON
-       stpt    __LC_EXIT_TIMER
+       stpt    __LC_EXIT_TIMER(%r13)
 .Lpgm_exit_kernel:
-       mvc     __LC_RETURN_PSW(16),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
+       mvc     __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
        LBEAR   STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)
        lmg     %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
        LPSWEY  __LC_RETURN_PSW,__LC_RETURN_LPSWE
@@ -378,11 +382,11 @@ SYM_CODE_START(pgm_check_handler)
 # single stepped system call
 #
 .Lpgm_svcper:
-       mvc     __LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
+       mvc     __LC_RETURN_PSW(8,%r13),__LC_SVC_NEW_PSW(%r13)
        larl    %r14,.Lsysc_per
-       stg     %r14,__LC_RETURN_PSW+8
+       stg     %r14,__LC_RETURN_PSW+8(%r13)
        lghi    %r14,1
-       LBEAR   __LC_PGM_LAST_BREAK
+       LBEAR   __LC_PGM_LAST_BREAK(%r13)
        LPSWEY  __LC_RETURN_PSW,__LC_RETURN_LPSWE # branch to .Lsysc_per
 SYM_CODE_END(pgm_check_handler)
 
@@ -596,7 +600,8 @@ SYM_CODE_END(restart_int_handler)
  * Setup a pt_regs so that show_trace can provide a good call trace.
  */
 SYM_CODE_START(stack_overflow)
-       lg      %r15,__LC_NODAT_STACK   # change to panic stack
+       GET_LC  %r15
+       lg      %r15,__LC_NODAT_STACK(%r15) # change to panic stack
        la      %r11,STACK_FRAME_OVERHEAD(%r15)
        stmg    %r0,%r7,__PT_R0(%r11)
        stmg    %r8,%r9,__PT_PSW(%r11)