[PATCH 3.16 145/192] sparc64: Fix bootup regressions on some Kconfig combinations.

Ben Hutchings
2017-10-09T13:17:38Z

From: "David S. Miller" <davem@davemloft.net>

[ Upstream commit 49fa5230462f9f2c4e97c81356473a6bdf06c422 ]

The system call tracing bug fix mentioned in the Fixes tag
below increased the amount of assembler code in the sequence
of assembler files included by head_64.S

This caused to total set of code to exceed 0x4000 bytes in
size, which overflows the expression in head_64.S that works
to place swapper_tsb at address 0x408000.

When this is violated, the TSB is not properly aligned, and
also the trap table is not aligned properly either. All of
this together results in failed boots.

So, do two things:

1) Simplify some code by using ba,a instead of ba/nop to get
those bytes back.

2) Add a linker script assertion to make sure that if this
happens again the build will fail.

Fixes: 1a40b95374f6 ("sparc: Fix system call tracing register handling.")
Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: Joerg Abraham <joerg.abraham@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
arch/sparc/kernel/cherrs.S | 14 +++++---------
arch/sparc/kernel/fpu_traps.S | 11 +++++------
arch/sparc/kernel/head_64.S | 24 ++++++++----------------
arch/sparc/kernel/misctrap.S | 12 ++++--------
arch/sparc/kernel/spiterrs.S | 18 ++++++------------
arch/sparc/kernel/utrap.S | 3 +--
arch/sparc/kernel/vmlinux.lds.S | 4 ++++
arch/sparc/kernel/winfixup.S | 3 +--
8 files changed, 34 insertions(+), 55 deletions(-)

--- a/arch/sparc/kernel/cherrs.S
+++ b/arch/sparc/kernel/cherrs.S
@@ -214,8 +214,7 @@ do_dcpe_tl1_nonfatal: /* Ok we may use i
subcc %g1, %g2, %g1 ! Next cacheline
bge,pt %icc, 1b
nop
- ba,pt %xcc, dcpe_icpe_tl1_common
- nop
+ ba,a,pt %xcc, dcpe_icpe_tl1_common

do_dcpe_tl1_fatal:
sethi %hi(1f), %g7
@@ -224,8 +223,7 @@ do_dcpe_tl1_fatal:
mov 0x2, %o0
call cheetah_plus_parity_error
add %sp, PTREGS_OFF, %o1
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size do_dcpe_tl1,.-do_dcpe_tl1

.globl do_icpe_tl1
@@ -259,8 +257,7 @@ do_icpe_tl1_nonfatal: /* Ok we may use i
subcc %g1, %g2, %g1
bge,pt %icc, 1b
nop
- ba,pt %xcc, dcpe_icpe_tl1_common
- nop
+ ba,a,pt %xcc, dcpe_icpe_tl1_common

do_icpe_tl1_fatal:
sethi %hi(1f), %g7
@@ -269,8 +266,7 @@ do_icpe_tl1_fatal:
mov 0x3, %o0
call cheetah_plus_parity_error
add %sp, PTREGS_OFF, %o1
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size do_icpe_tl1,.-do_icpe_tl1

.type dcpe_icpe_tl1_common,#function
@@ -456,7 +452,7 @@ __cheetah_log_error:
cmp %g2, 0x63
be c_cee
nop
- ba,pt %xcc, c_deferred
+ ba,a,pt %xcc, c_deferred
.size __cheetah_log_error,.-__cheetah_log_error

/* Cheetah FECC trap handling, we get here from tl{0,1}_fecc
--- a/arch/sparc/kernel/fpu_traps.S
+++ b/arch/sparc/kernel/fpu_traps.S
@@ -100,8 +100,8 @@ do_fpdis:
fmuld %f0, %f2, %f26
faddd %f0, %f2, %f28
fmuld %f0, %f2, %f30
- b,pt %xcc, fpdis_exit
- nop
+ ba,a,pt %xcc, fpdis_exit
+
2: andcc %g5, FPRS_DU, %g0
bne,pt %icc, 3f
fzero %f32
@@ -144,8 +144,8 @@ do_fpdis:
fmuld %f32, %f34, %f58
faddd %f32, %f34, %f60
fmuld %f32, %f34, %f62
- ba,pt %xcc, fpdis_exit
- nop
+ ba,a,pt %xcc, fpdis_exit
+
3: mov SECONDARY_CONTEXT, %g3
add %g6, TI_FPREGS, %g1

@@ -197,8 +197,7 @@ fpdis_exit2:
fp_other_bounce:
call do_fpother
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size fp_other_bounce,.-fp_other_bounce

.align 32
--- a/arch/sparc/kernel/head_64.S
+++ b/arch/sparc/kernel/head_64.S
@@ -461,9 +461,8 @@ sun4v_chip_type:
subcc %g3, 1, %g3
bne,pt %xcc, 41b
add %g1, 1, %g1
- mov SUN4V_CHIP_SPARC64X, %g4
ba,pt %xcc, 5f
- nop
+ mov SUN4V_CHIP_SPARC64X, %g4

49:
mov SUN4V_CHIP_UNKNOWN, %g4
@@ -548,8 +547,7 @@ sun4u_init:
stxa %g0, [%g7] ASI_DMMU
membar #Sync

- ba,pt %xcc, sun4u_continue
- nop
+ ba,a,pt %xcc, sun4u_continue

sun4v_init:
/* Set ctx 0 */
@@ -560,14 +558,12 @@ sun4v_init:
mov SECONDARY_CONTEXT, %g7
stxa %g0, [%g7] ASI_MMU
membar #Sync
- ba,pt %xcc, niagara_tlb_fixup
- nop
+ ba,a,pt %xcc, niagara_tlb_fixup

sun4u_continue:
BRANCH_IF_ANY_CHEETAH(g1, g7, cheetah_tlb_fixup)

- ba,pt %xcc, spitfire_tlb_fixup
- nop
+ ba,a,pt %xcc, spitfire_tlb_fixup

niagara_tlb_fixup:
mov 3, %g2 /* Set TLB type to hypervisor. */
@@ -639,8 +635,7 @@ niagara_patch:
call hypervisor_patch_cachetlbops
nop

- ba,pt %xcc, tlb_fixup_done
- nop
+ ba,a,pt %xcc, tlb_fixup_done

cheetah_tlb_fixup:
mov 2, %g2 /* Set TLB type to cheetah+. */
@@ -659,8 +654,7 @@ cheetah_tlb_fixup:
call cheetah_patch_cachetlbops
nop

- ba,pt %xcc, tlb_fixup_done
- nop
+ ba,a,pt %xcc, tlb_fixup_done

spitfire_tlb_fixup:
/* Set TLB type to spitfire. */
@@ -782,8 +776,7 @@ setup_trap_table:
call %o1
add %sp, (2047 + 128), %o0

- ba,pt %xcc, 2f
- nop
+ ba,a,pt %xcc, 2f

1: sethi %hi(sparc64_ttable_tl0), %o0
set prom_set_trap_table_name, %g2
@@ -822,8 +815,7 @@ setup_trap_table:

BRANCH_IF_ANY_CHEETAH(o2, o3, 1f)

- ba,pt %xcc, 2f
- nop
+ ba,a,pt %xcc, 2f

/* Disable STICK_INT interrupts. */
1:
--- a/arch/sparc/kernel/misctrap.S
+++ b/arch/sparc/kernel/misctrap.S
@@ -18,8 +18,7 @@ __do_privact:
109: or %g7, %lo(109b), %g7
call do_privact
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size __do_privact,.-__do_privact

.type do_mna,#function
@@ -46,8 +45,7 @@ do_mna:
mov %l5, %o2
call mem_address_unaligned
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size do_mna,.-do_mna

.type do_lddfmna,#function
@@ -65,8 +63,7 @@ do_lddfmna:
mov %l5, %o2
call handle_lddfmna
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size do_lddfmna,.-do_lddfmna

.type do_stdfmna,#function
@@ -84,8 +81,7 @@ do_stdfmna:
mov %l5, %o2
call handle_stdfmna
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size do_stdfmna,.-do_stdfmna

.type breakpoint_trap,#function
--- a/arch/sparc/kernel/spiterrs.S
+++ b/arch/sparc/kernel/spiterrs.S
@@ -85,8 +85,7 @@ __spitfire_cee_trap_continue:
ba,pt %xcc, etraptl1
rd %pc, %g7

- ba,pt %xcc, 2f
- nop
+ ba,a,pt %xcc, 2f

1: ba,pt %xcc, etrap_irq
rd %pc, %g7
@@ -100,8 +99,7 @@ __spitfire_cee_trap_continue:
mov %l5, %o2
call spitfire_access_error
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size __spitfire_access_error,.-__spitfire_access_error

/* This is the trap handler entry point for ECC correctable
@@ -179,8 +177,7 @@ __spitfire_data_access_exception_tl1:
mov %l5, %o2
call spitfire_data_access_exception_tl1
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size __spitfire_data_access_exception_tl1,.-__spitfire_data_access_exception_tl1

.type __spitfire_data_access_exception,#function
@@ -200,8 +197,7 @@ __spitfire_data_access_exception:
mov %l5, %o2
call spitfire_data_access_exception
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size __spitfire_data_access_exception,.-__spitfire_data_access_exception

.type __spitfire_insn_access_exception_tl1,#function
@@ -220,8 +216,7 @@ __spitfire_insn_access_exception_tl1:
mov %l5, %o2
call spitfire_insn_access_exception_tl1
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size __spitfire_insn_access_exception_tl1,.-__spitfire_insn_access_exception_tl1

.type __spitfire_insn_access_exception,#function
@@ -240,6 +235,5 @@ __spitfire_insn_access_exception:
mov %l5, %o2
call spitfire_insn_access_exception
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap
.size __spitfire_insn_access_exception,.-__spitfire_insn_access_exception
--- a/arch/sparc/kernel/utrap.S
+++ b/arch/sparc/kernel/utrap.S
@@ -11,8 +11,7 @@ utrap_trap: /* %g3=handler,%g4=level */
mov %l4, %o1
call bad_trap
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap

invoke_utrap:
sllx %g3, 3, %g3
--- a/arch/sparc/kernel/vmlinux.lds.S
+++ b/arch/sparc/kernel/vmlinux.lds.S
@@ -33,6 +33,10 @@ ENTRY(_start)
jiffies = jiffies_64;
#endif

+#ifdef CONFIG_SPARC64
+ASSERT((swapper_tsb == 0x0000000000408000), "Error: sparc64 early assembler too large")
+#endif
+
SECTIONS
{
#ifdef CONFIG_SPARC64
--- a/arch/sparc/kernel/winfixup.S
+++ b/arch/sparc/kernel/winfixup.S
@@ -32,8 +32,7 @@ fill_fixup:
rd %pc, %g7
call do_sparc64_fault
add %sp, PTREGS_OFF, %o0
- ba,pt %xcc, rtrap
- nop
+ ba,a,pt %xcc, rtrap

/* Be very careful about usage of the trap globals here.
* You cannot touch %g5 as that has the fault information.