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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:35:05 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:39:31 +0000
commit85c675d0d09a45a135bddd15d7b385f8758c32fb (patch)
tree76267dbc9b9a130337be3640948fe397b04ac629 /arch/ia64/kernel/unaligned.c
parentAdding upstream version 6.6.15. (diff)
downloadlinux-85c675d0d09a45a135bddd15d7b385f8758c32fb.tar.xz
linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.zip
Adding upstream version 6.7.7.upstream/6.7.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/ia64/kernel/unaligned.c')
-rw-r--r--arch/ia64/kernel/unaligned.c1560
1 files changed, 0 insertions, 1560 deletions
diff --git a/arch/ia64/kernel/unaligned.c b/arch/ia64/kernel/unaligned.c
deleted file mode 100644
index 0acb5a0cd7..0000000000
--- a/arch/ia64/kernel/unaligned.c
+++ /dev/null
@@ -1,1560 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Architecture-specific unaligned trap handling.
- *
- * Copyright (C) 1999-2002, 2004 Hewlett-Packard Co
- * Stephane Eranian <eranian@hpl.hp.com>
- * David Mosberger-Tang <davidm@hpl.hp.com>
- *
- * 2002/12/09 Fix rotating register handling (off-by-1 error, missing fr-rotation). Fix
- * get_rse_reg() to not leak kernel bits to user-level (reading an out-of-frame
- * stacked register returns an undefined value; it does NOT trigger a
- * "rsvd register fault").
- * 2001/10/11 Fix unaligned access to rotating registers in s/w pipelined loops.
- * 2001/08/13 Correct size of extended floats (float_fsz) from 16 to 10 bytes.
- * 2001/01/17 Add support emulation of unaligned kernel accesses.
- */
-#include <linux/jiffies.h>
-#include <linux/kernel.h>
-#include <linux/sched/signal.h>
-#include <linux/tty.h>
-#include <linux/extable.h>
-#include <linux/ratelimit.h>
-#include <linux/uaccess.h>
-
-#include <asm/intrinsics.h>
-#include <asm/processor.h>
-#include <asm/rse.h>
-#include <asm/exception.h>
-#include <asm/unaligned.h>
-
-extern int die_if_kernel(char *str, struct pt_regs *regs, long err);
-
-#undef DEBUG_UNALIGNED_TRAP
-
-#ifdef DEBUG_UNALIGNED_TRAP
-# define DPRINT(a...) do { printk("%s %u: ", __func__, __LINE__); printk (a); } while (0)
-# define DDUMP(str,vp,len) dump(str, vp, len)
-
-static void
-dump (const char *str, void *vp, size_t len)
-{
- unsigned char *cp = vp;
- int i;
-
- printk("%s", str);
- for (i = 0; i < len; ++i)
- printk (" %02x", *cp++);
- printk("\n");
-}
-#else
-# define DPRINT(a...)
-# define DDUMP(str,vp,len)
-#endif
-
-#define IA64_FIRST_STACKED_GR 32
-#define IA64_FIRST_ROTATING_FR 32
-#define SIGN_EXT9 0xffffffffffffff00ul
-
-/*
- * sysctl settable hook which tells the kernel whether to honor the
- * IA64_THREAD_UAC_NOPRINT prctl. Because this is user settable, we want
- * to allow the super user to enable/disable this for security reasons
- * (i.e. don't allow attacker to fill up logs with unaligned accesses).
- */
-int no_unaligned_warning;
-int unaligned_dump_stack;
-
-/*
- * For M-unit:
- *
- * opcode | m | x6 |
- * --------|------|---------|
- * [40-37] | [36] | [35:30] |
- * --------|------|---------|
- * 4 | 1 | 6 | = 11 bits
- * --------------------------
- * However bits [31:30] are not directly useful to distinguish between
- * load/store so we can use [35:32] instead, which gives the following
- * mask ([40:32]) using 9 bits. The 'e' comes from the fact that we defer
- * checking the m-bit until later in the load/store emulation.
- */
-#define IA64_OPCODE_MASK 0x1ef
-#define IA64_OPCODE_SHIFT 32
-
-/*
- * Table C-28 Integer Load/Store
- *
- * We ignore [35:32]= 0x6, 0x7, 0xE, 0xF
- *
- * ld8.fill, st8.fill MUST be aligned because the RNATs are based on
- * the address (bits [8:3]), so we must failed.
- */
-#define LD_OP 0x080
-#define LDS_OP 0x081
-#define LDA_OP 0x082
-#define LDSA_OP 0x083
-#define LDBIAS_OP 0x084
-#define LDACQ_OP 0x085
-/* 0x086, 0x087 are not relevant */
-#define LDCCLR_OP 0x088
-#define LDCNC_OP 0x089
-#define LDCCLRACQ_OP 0x08a
-#define ST_OP 0x08c
-#define STREL_OP 0x08d
-/* 0x08e,0x8f are not relevant */
-
-/*
- * Table C-29 Integer Load +Reg
- *
- * we use the ld->m (bit [36:36]) field to determine whether or not we have
- * a load/store of this form.
- */
-
-/*
- * Table C-30 Integer Load/Store +Imm
- *
- * We ignore [35:32]= 0x6, 0x7, 0xE, 0xF
- *
- * ld8.fill, st8.fill must be aligned because the Nat register are based on
- * the address, so we must fail and the program must be fixed.
- */
-#define LD_IMM_OP 0x0a0
-#define LDS_IMM_OP 0x0a1
-#define LDA_IMM_OP 0x0a2
-#define LDSA_IMM_OP 0x0a3
-#define LDBIAS_IMM_OP 0x0a4
-#define LDACQ_IMM_OP 0x0a5
-/* 0x0a6, 0xa7 are not relevant */
-#define LDCCLR_IMM_OP 0x0a8
-#define LDCNC_IMM_OP 0x0a9
-#define LDCCLRACQ_IMM_OP 0x0aa
-#define ST_IMM_OP 0x0ac
-#define STREL_IMM_OP 0x0ad
-/* 0x0ae,0xaf are not relevant */
-
-/*
- * Table C-32 Floating-point Load/Store
- */
-#define LDF_OP 0x0c0
-#define LDFS_OP 0x0c1
-#define LDFA_OP 0x0c2
-#define LDFSA_OP 0x0c3
-/* 0x0c6 is irrelevant */
-#define LDFCCLR_OP 0x0c8
-#define LDFCNC_OP 0x0c9
-/* 0x0cb is irrelevant */
-#define STF_OP 0x0cc
-
-/*
- * Table C-33 Floating-point Load +Reg
- *
- * we use the ld->m (bit [36:36]) field to determine whether or not we have
- * a load/store of this form.
- */
-
-/*
- * Table C-34 Floating-point Load/Store +Imm
- */
-#define LDF_IMM_OP 0x0e0
-#define LDFS_IMM_OP 0x0e1
-#define LDFA_IMM_OP 0x0e2
-#define LDFSA_IMM_OP 0x0e3
-/* 0x0e6 is irrelevant */
-#define LDFCCLR_IMM_OP 0x0e8
-#define LDFCNC_IMM_OP 0x0e9
-#define STF_IMM_OP 0x0ec
-
-typedef struct {
- unsigned long qp:6; /* [0:5] */
- unsigned long r1:7; /* [6:12] */
- unsigned long imm:7; /* [13:19] */
- unsigned long r3:7; /* [20:26] */
- unsigned long x:1; /* [27:27] */
- unsigned long hint:2; /* [28:29] */
- unsigned long x6_sz:2; /* [30:31] */
- unsigned long x6_op:4; /* [32:35], x6 = x6_sz|x6_op */
- unsigned long m:1; /* [36:36] */
- unsigned long op:4; /* [37:40] */
- unsigned long pad:23; /* [41:63] */
-} load_store_t;
-
-
-typedef enum {
- UPD_IMMEDIATE, /* ldXZ r1=[r3],imm(9) */
- UPD_REG /* ldXZ r1=[r3],r2 */
-} update_t;
-
-/*
- * We use tables to keep track of the offsets of registers in the saved state.
- * This way we save having big switch/case statements.
- *
- * We use bit 0 to indicate switch_stack or pt_regs.
- * The offset is simply shifted by 1 bit.
- * A 2-byte value should be enough to hold any kind of offset
- *
- * In case the calling convention changes (and thus pt_regs/switch_stack)
- * simply use RSW instead of RPT or vice-versa.
- */
-
-#define RPO(x) ((size_t) &((struct pt_regs *)0)->x)
-#define RSO(x) ((size_t) &((struct switch_stack *)0)->x)
-
-#define RPT(x) (RPO(x) << 1)
-#define RSW(x) (1| RSO(x)<<1)
-
-#define GR_OFFS(x) (gr_info[x]>>1)
-#define GR_IN_SW(x) (gr_info[x] & 0x1)
-
-#define FR_OFFS(x) (fr_info[x]>>1)
-#define FR_IN_SW(x) (fr_info[x] & 0x1)
-
-static u16 gr_info[32]={
- 0, /* r0 is read-only : WE SHOULD NEVER GET THIS */
-
- RPT(r1), RPT(r2), RPT(r3),
-
- RSW(r4), RSW(r5), RSW(r6), RSW(r7),
-
- RPT(r8), RPT(r9), RPT(r10), RPT(r11),
- RPT(r12), RPT(r13), RPT(r14), RPT(r15),
-
- RPT(r16), RPT(r17), RPT(r18), RPT(r19),
- RPT(r20), RPT(r21), RPT(r22), RPT(r23),
- RPT(r24), RPT(r25), RPT(r26), RPT(r27),
- RPT(r28), RPT(r29), RPT(r30), RPT(r31)
-};
-
-static u16 fr_info[32]={
- 0, /* constant : WE SHOULD NEVER GET THIS */
- 0, /* constant : WE SHOULD NEVER GET THIS */
-
- RSW(f2), RSW(f3), RSW(f4), RSW(f5),
-
- RPT(f6), RPT(f7), RPT(f8), RPT(f9),
- RPT(f10), RPT(f11),
-
- RSW(f12), RSW(f13), RSW(f14),
- RSW(f15), RSW(f16), RSW(f17), RSW(f18), RSW(f19),
- RSW(f20), RSW(f21), RSW(f22), RSW(f23), RSW(f24),
- RSW(f25), RSW(f26), RSW(f27), RSW(f28), RSW(f29),
- RSW(f30), RSW(f31)
-};
-
-/* Invalidate ALAT entry for integer register REGNO. */
-static void
-invala_gr (int regno)
-{
-# define F(reg) case reg: ia64_invala_gr(reg); break
-
- switch (regno) {
- F( 0); F( 1); F( 2); F( 3); F( 4); F( 5); F( 6); F( 7);
- F( 8); F( 9); F( 10); F( 11); F( 12); F( 13); F( 14); F( 15);
- F( 16); F( 17); F( 18); F( 19); F( 20); F( 21); F( 22); F( 23);
- F( 24); F( 25); F( 26); F( 27); F( 28); F( 29); F( 30); F( 31);
- F( 32); F( 33); F( 34); F( 35); F( 36); F( 37); F( 38); F( 39);
- F( 40); F( 41); F( 42); F( 43); F( 44); F( 45); F( 46); F( 47);
- F( 48); F( 49); F( 50); F( 51); F( 52); F( 53); F( 54); F( 55);
- F( 56); F( 57); F( 58); F( 59); F( 60); F( 61); F( 62); F( 63);
- F( 64); F( 65); F( 66); F( 67); F( 68); F( 69); F( 70); F( 71);
- F( 72); F( 73); F( 74); F( 75); F( 76); F( 77); F( 78); F( 79);
- F( 80); F( 81); F( 82); F( 83); F( 84); F( 85); F( 86); F( 87);
- F( 88); F( 89); F( 90); F( 91); F( 92); F( 93); F( 94); F( 95);
- F( 96); F( 97); F( 98); F( 99); F(100); F(101); F(102); F(103);
- F(104); F(105); F(106); F(107); F(108); F(109); F(110); F(111);
- F(112); F(113); F(114); F(115); F(116); F(117); F(118); F(119);
- F(120); F(121); F(122); F(123); F(124); F(125); F(126); F(127);
- }
-# undef F
-}
-
-/* Invalidate ALAT entry for floating-point register REGNO. */
-static void
-invala_fr (int regno)
-{
-# define F(reg) case reg: ia64_invala_fr(reg); break
-
- switch (regno) {
- F( 0); F( 1); F( 2); F( 3); F( 4); F( 5); F( 6); F( 7);
- F( 8); F( 9); F( 10); F( 11); F( 12); F( 13); F( 14); F( 15);
- F( 16); F( 17); F( 18); F( 19); F( 20); F( 21); F( 22); F( 23);
- F( 24); F( 25); F( 26); F( 27); F( 28); F( 29); F( 30); F( 31);
- F( 32); F( 33); F( 34); F( 35); F( 36); F( 37); F( 38); F( 39);
- F( 40); F( 41); F( 42); F( 43); F( 44); F( 45); F( 46); F( 47);
- F( 48); F( 49); F( 50); F( 51); F( 52); F( 53); F( 54); F( 55);
- F( 56); F( 57); F( 58); F( 59); F( 60); F( 61); F( 62); F( 63);
- F( 64); F( 65); F( 66); F( 67); F( 68); F( 69); F( 70); F( 71);
- F( 72); F( 73); F( 74); F( 75); F( 76); F( 77); F( 78); F( 79);
- F( 80); F( 81); F( 82); F( 83); F( 84); F( 85); F( 86); F( 87);
- F( 88); F( 89); F( 90); F( 91); F( 92); F( 93); F( 94); F( 95);
- F( 96); F( 97); F( 98); F( 99); F(100); F(101); F(102); F(103);
- F(104); F(105); F(106); F(107); F(108); F(109); F(110); F(111);
- F(112); F(113); F(114); F(115); F(116); F(117); F(118); F(119);
- F(120); F(121); F(122); F(123); F(124); F(125); F(126); F(127);
- }
-# undef F
-}
-
-static inline unsigned long
-rotate_reg (unsigned long sor, unsigned long rrb, unsigned long reg)
-{
- reg += rrb;
- if (reg >= sor)
- reg -= sor;
- return reg;
-}
-
-static void
-set_rse_reg (struct pt_regs *regs, unsigned long r1, unsigned long val, int nat)
-{
- struct switch_stack *sw = (struct switch_stack *) regs - 1;
- unsigned long *bsp, *bspstore, *addr, *rnat_addr, *ubs_end;
- unsigned long *kbs = (void *) current + IA64_RBS_OFFSET;
- unsigned long rnats, nat_mask;
- unsigned long on_kbs;
- long sof = (regs->cr_ifs) & 0x7f;
- long sor = 8 * ((regs->cr_ifs >> 14) & 0xf);
- long rrb_gr = (regs->cr_ifs >> 18) & 0x7f;
- long ridx = r1 - 32;
-
- if (ridx >= sof) {
- /* this should never happen, as the "rsvd register fault" has higher priority */
- DPRINT("ignoring write to r%lu; only %lu registers are allocated!\n", r1, sof);
- return;
- }
-
- if (ridx < sor)
- ridx = rotate_reg(sor, rrb_gr, ridx);
-
- DPRINT("r%lu, sw.bspstore=%lx pt.bspstore=%lx sof=%ld sol=%ld ridx=%ld\n",
- r1, sw->ar_bspstore, regs->ar_bspstore, sof, (regs->cr_ifs >> 7) & 0x7f, ridx);
-
- on_kbs = ia64_rse_num_regs(kbs, (unsigned long *) sw->ar_bspstore);
- addr = ia64_rse_skip_regs((unsigned long *) sw->ar_bspstore, -sof + ridx);
- if (addr >= kbs) {
- /* the register is on the kernel backing store: easy... */
- rnat_addr = ia64_rse_rnat_addr(addr);
- if ((unsigned long) rnat_addr >= sw->ar_bspstore)
- rnat_addr = &sw->ar_rnat;
- nat_mask = 1UL << ia64_rse_slot_num(addr);
-
- *addr = val;
- if (nat)
- *rnat_addr |= nat_mask;
- else
- *rnat_addr &= ~nat_mask;
- return;
- }
-
- if (!user_stack(current, regs)) {
- DPRINT("ignoring kernel write to r%lu; register isn't on the kernel RBS!", r1);
- return;
- }
-
- bspstore = (unsigned long *)regs->ar_bspstore;
- ubs_end = ia64_rse_skip_regs(bspstore, on_kbs);
- bsp = ia64_rse_skip_regs(ubs_end, -sof);
- addr = ia64_rse_skip_regs(bsp, ridx);
-
- DPRINT("ubs_end=%p bsp=%p addr=%p\n", (void *) ubs_end, (void *) bsp, (void *) addr);
-
- ia64_poke(current, sw, (unsigned long) ubs_end, (unsigned long) addr, val);
-
- rnat_addr = ia64_rse_rnat_addr(addr);
-
- ia64_peek(current, sw, (unsigned long) ubs_end, (unsigned long) rnat_addr, &rnats);
- DPRINT("rnat @%p = 0x%lx nat=%d old nat=%ld\n",
- (void *) rnat_addr, rnats, nat, (rnats >> ia64_rse_slot_num(addr)) & 1);
-
- nat_mask = 1UL << ia64_rse_slot_num(addr);
- if (nat)
- rnats |= nat_mask;
- else
- rnats &= ~nat_mask;
- ia64_poke(current, sw, (unsigned long) ubs_end, (unsigned long) rnat_addr, rnats);
-
- DPRINT("rnat changed to @%p = 0x%lx\n", (void *) rnat_addr, rnats);
-}
-
-
-static void
-get_rse_reg (struct pt_regs *regs, unsigned long r1, unsigned long *val, int *nat)
-{
- struct switch_stack *sw = (struct switch_stack *) regs - 1;
- unsigned long *bsp, *addr, *rnat_addr, *ubs_end, *bspstore;
- unsigned long *kbs = (void *) current + IA64_RBS_OFFSET;
- unsigned long rnats, nat_mask;
- unsigned long on_kbs;
- long sof = (regs->cr_ifs) & 0x7f;
- long sor = 8 * ((regs->cr_ifs >> 14) & 0xf);
- long rrb_gr = (regs->cr_ifs >> 18) & 0x7f;
- long ridx = r1 - 32;
-
- if (ridx >= sof) {
- /* read of out-of-frame register returns an undefined value; 0 in our case. */
- DPRINT("ignoring read from r%lu; only %lu registers are allocated!\n", r1, sof);
- goto fail;
- }
-
- if (ridx < sor)
- ridx = rotate_reg(sor, rrb_gr, ridx);
-
- DPRINT("r%lu, sw.bspstore=%lx pt.bspstore=%lx sof=%ld sol=%ld ridx=%ld\n",
- r1, sw->ar_bspstore, regs->ar_bspstore, sof, (regs->cr_ifs >> 7) & 0x7f, ridx);
-
- on_kbs = ia64_rse_num_regs(kbs, (unsigned long *) sw->ar_bspstore);
- addr = ia64_rse_skip_regs((unsigned long *) sw->ar_bspstore, -sof + ridx);
- if (addr >= kbs) {
- /* the register is on the kernel backing store: easy... */
- *val = *addr;
- if (nat) {
- rnat_addr = ia64_rse_rnat_addr(addr);
- if ((unsigned long) rnat_addr >= sw->ar_bspstore)
- rnat_addr = &sw->ar_rnat;
- nat_mask = 1UL << ia64_rse_slot_num(addr);
- *nat = (*rnat_addr & nat_mask) != 0;
- }
- return;
- }
-
- if (!user_stack(current, regs)) {
- DPRINT("ignoring kernel read of r%lu; register isn't on the RBS!", r1);
- goto fail;
- }
-
- bspstore = (unsigned long *)regs->ar_bspstore;
- ubs_end = ia64_rse_skip_regs(bspstore, on_kbs);
- bsp = ia64_rse_skip_regs(ubs_end, -sof);
- addr = ia64_rse_skip_regs(bsp, ridx);
-
- DPRINT("ubs_end=%p bsp=%p addr=%p\n", (void *) ubs_end, (void *) bsp, (void *) addr);
-
- ia64_peek(current, sw, (unsigned long) ubs_end, (unsigned long) addr, val);
-
- if (nat) {
- rnat_addr = ia64_rse_rnat_addr(addr);
- nat_mask = 1UL << ia64_rse_slot_num(addr);
-
- DPRINT("rnat @%p = 0x%lx\n", (void *) rnat_addr, rnats);
-
- ia64_peek(current, sw, (unsigned long) ubs_end, (unsigned long) rnat_addr, &rnats);
- *nat = (rnats & nat_mask) != 0;
- }
- return;
-
- fail:
- *val = 0;
- if (nat)
- *nat = 0;
- return;
-}
-
-
-static void
-setreg (unsigned long regnum, unsigned long val, int nat, struct pt_regs *regs)
-{
- struct switch_stack *sw = (struct switch_stack *) regs - 1;
- unsigned long addr;
- unsigned long bitmask;
- unsigned long *unat;
-
- /*
- * First takes care of stacked registers
- */
- if (regnum >= IA64_FIRST_STACKED_GR) {
- set_rse_reg(regs, regnum, val, nat);
- return;
- }
-
- /*
- * Using r0 as a target raises a General Exception fault which has higher priority
- * than the Unaligned Reference fault.
- */
-
- /*
- * Now look at registers in [0-31] range and init correct UNAT
- */
- if (GR_IN_SW(regnum)) {
- addr = (unsigned long)sw;
- unat = &sw->ar_unat;
- } else {
- addr = (unsigned long)regs;
- unat = &sw->caller_unat;
- }
- DPRINT("tmp_base=%lx switch_stack=%s offset=%d\n",
- addr, unat==&sw->ar_unat ? "yes":"no", GR_OFFS(regnum));
- /*
- * add offset from base of struct
- * and do it !
- */
- addr += GR_OFFS(regnum);
-
- *(unsigned long *)addr = val;
-
- /*
- * We need to clear the corresponding UNAT bit to fully emulate the load
- * UNAT bit_pos = GR[r3]{8:3} form EAS-2.4
- */
- bitmask = 1UL << (addr >> 3 & 0x3f);
- DPRINT("*0x%lx=0x%lx NaT=%d prev_unat @%p=%lx\n", addr, val, nat, (void *) unat, *unat);
- if (nat) {
- *unat |= bitmask;
- } else {
- *unat &= ~bitmask;
- }
- DPRINT("*0x%lx=0x%lx NaT=%d new unat: %p=%lx\n", addr, val, nat, (void *) unat,*unat);
-}
-
-/*
- * Return the (rotated) index for floating point register REGNUM (REGNUM must be in the
- * range from 32-127, result is in the range from 0-95.
- */
-static inline unsigned long
-fph_index (struct pt_regs *regs, long regnum)
-{
- unsigned long rrb_fr = (regs->cr_ifs >> 25) & 0x7f;
- return rotate_reg(96, rrb_fr, (regnum - IA64_FIRST_ROTATING_FR));
-}
-
-static void
-setfpreg (unsigned long regnum, struct ia64_fpreg *fpval, struct pt_regs *regs)
-{
- struct switch_stack *sw = (struct switch_stack *)regs - 1;
- unsigned long addr;
-
- /*
- * From EAS-2.5: FPDisableFault has higher priority than Unaligned
- * Fault. Thus, when we get here, we know the partition is enabled.
- * To update f32-f127, there are three choices:
- *
- * (1) save f32-f127 to thread.fph and update the values there
- * (2) use a gigantic switch statement to directly access the registers
- * (3) generate code on the fly to update the desired register
- *
- * For now, we are using approach (1).
- */
- if (regnum >= IA64_FIRST_ROTATING_FR) {
- ia64_sync_fph(current);
- current->thread.fph[fph_index(regs, regnum)] = *fpval;
- } else {
- /*
- * pt_regs or switch_stack ?
- */
- if (FR_IN_SW(regnum)) {
- addr = (unsigned long)sw;
- } else {
- addr = (unsigned long)regs;
- }
-
- DPRINT("tmp_base=%lx offset=%d\n", addr, FR_OFFS(regnum));
-
- addr += FR_OFFS(regnum);
- *(struct ia64_fpreg *)addr = *fpval;
-
- /*
- * mark the low partition as being used now
- *
- * It is highly unlikely that this bit is not already set, but
- * let's do it for safety.
- */
- regs->cr_ipsr |= IA64_PSR_MFL;
- }
-}
-
-/*
- * Those 2 inline functions generate the spilled versions of the constant floating point
- * registers which can be used with stfX
- */
-static inline void
-float_spill_f0 (struct ia64_fpreg *final)
-{
- ia64_stf_spill(final, 0);
-}
-
-static inline void
-float_spill_f1 (struct ia64_fpreg *final)
-{
- ia64_stf_spill(final, 1);
-}
-
-static void
-getfpreg (unsigned long regnum, struct ia64_fpreg *fpval, struct pt_regs *regs)
-{
- struct switch_stack *sw = (struct switch_stack *) regs - 1;
- unsigned long addr;
-
- /*
- * From EAS-2.5: FPDisableFault has higher priority than
- * Unaligned Fault. Thus, when we get here, we know the partition is
- * enabled.
- *
- * When regnum > 31, the register is still live and we need to force a save
- * to current->thread.fph to get access to it. See discussion in setfpreg()
- * for reasons and other ways of doing this.
- */
- if (regnum >= IA64_FIRST_ROTATING_FR) {
- ia64_flush_fph(current);
- *fpval = current->thread.fph[fph_index(regs, regnum)];
- } else {
- /*
- * f0 = 0.0, f1= 1.0. Those registers are constant and are thus
- * not saved, we must generate their spilled form on the fly
- */
- switch(regnum) {
- case 0:
- float_spill_f0(fpval);
- break;
- case 1:
- float_spill_f1(fpval);
- break;
- default:
- /*
- * pt_regs or switch_stack ?
- */
- addr = FR_IN_SW(regnum) ? (unsigned long)sw
- : (unsigned long)regs;
-
- DPRINT("is_sw=%d tmp_base=%lx offset=0x%x\n",
- FR_IN_SW(regnum), addr, FR_OFFS(regnum));
-
- addr += FR_OFFS(regnum);
- *fpval = *(struct ia64_fpreg *)addr;
- }
- }
-}
-
-
-static void
-getreg (unsigned long regnum, unsigned long *val, int *nat, struct pt_regs *regs)
-{
- struct switch_stack *sw = (struct switch_stack *) regs - 1;
- unsigned long addr, *unat;
-
- if (regnum >= IA64_FIRST_STACKED_GR) {
- get_rse_reg(regs, regnum, val, nat);
- return;
- }
-
- /*
- * take care of r0 (read-only always evaluate to 0)
- */
- if (regnum == 0) {
- *val = 0;
- if (nat)
- *nat = 0;
- return;
- }
-
- /*
- * Now look at registers in [0-31] range and init correct UNAT
- */
- if (GR_IN_SW(regnum)) {
- addr = (unsigned long)sw;
- unat = &sw->ar_unat;
- } else {
- addr = (unsigned long)regs;
- unat = &sw->caller_unat;
- }
-
- DPRINT("addr_base=%lx offset=0x%x\n", addr, GR_OFFS(regnum));
-
- addr += GR_OFFS(regnum);
-
- *val = *(unsigned long *)addr;
-
- /*
- * do it only when requested
- */
- if (nat)
- *nat = (*unat >> (addr >> 3 & 0x3f)) & 0x1UL;
-}
-
-static void
-emulate_load_updates (update_t type, load_store_t ld, struct pt_regs *regs, unsigned long ifa)
-{
- /*
- * IMPORTANT:
- * Given the way we handle unaligned speculative loads, we should
- * not get to this point in the code but we keep this sanity check,
- * just in case.
- */
- if (ld.x6_op == 1 || ld.x6_op == 3) {
- printk(KERN_ERR "%s: register update on speculative load, error\n", __func__);
- if (die_if_kernel("unaligned reference on speculative load with register update\n",
- regs, 30))
- return;
- }
-
-
- /*
- * at this point, we know that the base register to update is valid i.e.,
- * it's not r0
- */
- if (type == UPD_IMMEDIATE) {
- unsigned long imm;
-
- /*
- * Load +Imm: ldXZ r1=[r3],imm(9)
- *
- *
- * form imm9: [13:19] contain the first 7 bits
- */
- imm = ld.x << 7 | ld.imm;
-
- /*
- * sign extend (1+8bits) if m set
- */
- if (ld.m) imm |= SIGN_EXT9;
-
- /*
- * ifa == r3 and we know that the NaT bit on r3 was clear so
- * we can directly use ifa.
- */
- ifa += imm;
-
- setreg(ld.r3, ifa, 0, regs);
-
- DPRINT("ld.x=%d ld.m=%d imm=%ld r3=0x%lx\n", ld.x, ld.m, imm, ifa);
-
- } else if (ld.m) {
- unsigned long r2;
- int nat_r2;
-
- /*
- * Load +Reg Opcode: ldXZ r1=[r3],r2
- *
- * Note: that we update r3 even in the case of ldfX.a
- * (where the load does not happen)
- *
- * The way the load algorithm works, we know that r3 does not
- * have its NaT bit set (would have gotten NaT consumption
- * before getting the unaligned fault). So we can use ifa
- * which equals r3 at this point.
- *
- * IMPORTANT:
- * The above statement holds ONLY because we know that we
- * never reach this code when trying to do a ldX.s.
- * If we ever make it to here on an ldfX.s then
- */
- getreg(ld.imm, &r2, &nat_r2, regs);
-
- ifa += r2;
-
- /*
- * propagate Nat r2 -> r3
- */
- setreg(ld.r3, ifa, nat_r2, regs);
-
- DPRINT("imm=%d r2=%ld r3=0x%lx nat_r2=%d\n",ld.imm, r2, ifa, nat_r2);
- }
-}
-
-static int emulate_store(unsigned long ifa, void *val, int len, bool kernel_mode)
-{
- if (kernel_mode)
- return copy_to_kernel_nofault((void *)ifa, val, len);
-
- return copy_to_user((void __user *)ifa, val, len);
-}
-
-static int emulate_load(void *val, unsigned long ifa, int len, bool kernel_mode)
-{
- if (kernel_mode)
- return copy_from_kernel_nofault(val, (void *)ifa, len);
-
- return copy_from_user(val, (void __user *)ifa, len);
-}
-
-static int
-emulate_load_int (unsigned long ifa, load_store_t ld, struct pt_regs *regs,
- bool kernel_mode)
-{
- unsigned int len = 1 << ld.x6_sz;
- unsigned long val = 0;
-
- /*
- * r0, as target, doesn't need to be checked because Illegal Instruction
- * faults have higher priority than unaligned faults.
- *
- * r0 cannot be found as the base as it would never generate an
- * unaligned reference.
- */
-
- /*
- * ldX.a we will emulate load and also invalidate the ALAT entry.
- * See comment below for explanation on how we handle ldX.a
- */
-
- if (len != 2 && len != 4 && len != 8) {
- DPRINT("unknown size: x6=%d\n", ld.x6_sz);
- return -1;
- }
- /* this assumes little-endian byte-order: */
- if (emulate_load(&val, ifa, len, kernel_mode))
- return -1;
- setreg(ld.r1, val, 0, regs);
-
- /*
- * check for updates on any kind of loads
- */
- if (ld.op == 0x5 || ld.m)
- emulate_load_updates(ld.op == 0x5 ? UPD_IMMEDIATE: UPD_REG, ld, regs, ifa);
-
- /*
- * handling of various loads (based on EAS2.4):
- *
- * ldX.acq (ordered load):
- * - acquire semantics would have been used, so force fence instead.
- *
- * ldX.c.clr (check load and clear):
- * - if we get to this handler, it's because the entry was not in the ALAT.
- * Therefore the operation reverts to a normal load
- *
- * ldX.c.nc (check load no clear):
- * - same as previous one
- *
- * ldX.c.clr.acq (ordered check load and clear):
- * - same as above for c.clr part. The load needs to have acquire semantics. So
- * we use the fence semantics which is stronger and thus ensures correctness.
- *
- * ldX.a (advanced load):
- * - suppose ldX.a r1=[r3]. If we get to the unaligned trap it's because the
- * address doesn't match requested size alignment. This means that we would
- * possibly need more than one load to get the result.
- *
- * The load part can be handled just like a normal load, however the difficult
- * part is to get the right thing into the ALAT. The critical piece of information
- * in the base address of the load & size. To do that, a ld.a must be executed,
- * clearly any address can be pushed into the table by using ld1.a r1=[r3]. Now
- * if we use the same target register, we will be okay for the check.a instruction.
- * If we look at the store, basically a stX [r3]=r1 checks the ALAT for any entry
- * which would overlap within [r3,r3+X] (the size of the load was store in the
- * ALAT). If such an entry is found the entry is invalidated. But this is not good
- * enough, take the following example:
- * r3=3
- * ld4.a r1=[r3]
- *
- * Could be emulated by doing:
- * ld1.a r1=[r3],1
- * store to temporary;
- * ld1.a r1=[r3],1
- * store & shift to temporary;
- * ld1.a r1=[r3],1
- * store & shift to temporary;
- * ld1.a r1=[r3]
- * store & shift to temporary;
- * r1=temporary
- *
- * So in this case, you would get the right value is r1 but the wrong info in
- * the ALAT. Notice that you could do it in reverse to finish with address 3
- * but you would still get the size wrong. To get the size right, one needs to
- * execute exactly the same kind of load. You could do it from a aligned
- * temporary location, but you would get the address wrong.
- *
- * So no matter what, it is not possible to emulate an advanced load
- * correctly. But is that really critical ?
- *
- * We will always convert ld.a into a normal load with ALAT invalidated. This
- * will enable compiler to do optimization where certain code path after ld.a
- * is not required to have ld.c/chk.a, e.g., code path with no intervening stores.
- *
- * If there is a store after the advanced load, one must either do a ld.c.* or
- * chk.a.* to reuse the value stored in the ALAT. Both can "fail" (meaning no
- * entry found in ALAT), and that's perfectly ok because:
- *
- * - ld.c.*, if the entry is not present a normal load is executed
- * - chk.a.*, if the entry is not present, execution jumps to recovery code
- *
- * In either case, the load can be potentially retried in another form.
- *
- * ALAT must be invalidated for the register (so that chk.a or ld.c don't pick
- * up a stale entry later). The register base update MUST also be performed.
- */
-
- /*
- * when the load has the .acq completer then
- * use ordering fence.
- */
- if (ld.x6_op == 0x5 || ld.x6_op == 0xa)
- mb();
-
- /*
- * invalidate ALAT entry in case of advanced load
- */
- if (ld.x6_op == 0x2)
- invala_gr(ld.r1);
-
- return 0;
-}
-
-static int
-emulate_store_int (unsigned long ifa, load_store_t ld, struct pt_regs *regs,
- bool kernel_mode)
-{
- unsigned long r2;
- unsigned int len = 1 << ld.x6_sz;
-
- /*
- * if we get to this handler, Nat bits on both r3 and r2 have already
- * been checked. so we don't need to do it
- *
- * extract the value to be stored
- */
- getreg(ld.imm, &r2, NULL, regs);
-
- /*
- * we rely on the macros in unaligned.h for now i.e.,
- * we let the compiler figure out how to read memory gracefully.
- *
- * We need this switch/case because the way the inline function
- * works. The code is optimized by the compiler and looks like
- * a single switch/case.
- */
- DPRINT("st%d [%lx]=%lx\n", len, ifa, r2);
-
- if (len != 2 && len != 4 && len != 8) {
- DPRINT("unknown size: x6=%d\n", ld.x6_sz);
- return -1;
- }
-
- /* this assumes little-endian byte-order: */
- if (emulate_store(ifa, &r2, len, kernel_mode))
- return -1;
-
- /*
- * stX [r3]=r2,imm(9)
- *
- * NOTE:
- * ld.r3 can never be r0, because r0 would not generate an
- * unaligned access.
- */
- if (ld.op == 0x5) {
- unsigned long imm;
-
- /*
- * form imm9: [12:6] contain first 7bits
- */
- imm = ld.x << 7 | ld.r1;
- /*
- * sign extend (8bits) if m set
- */
- if (ld.m) imm |= SIGN_EXT9;
- /*
- * ifa == r3 (NaT is necessarily cleared)
- */
- ifa += imm;
-
- DPRINT("imm=%lx r3=%lx\n", imm, ifa);
-
- setreg(ld.r3, ifa, 0, regs);
- }
- /*
- * we don't have alat_invalidate_multiple() so we need
- * to do the complete flush :-<<
- */
- ia64_invala();
-
- /*
- * stX.rel: use fence instead of release
- */
- if (ld.x6_op == 0xd)
- mb();
-
- return 0;
-}
-
-/*
- * floating point operations sizes in bytes
- */
-static const unsigned char float_fsz[4]={
- 10, /* extended precision (e) */
- 8, /* integer (8) */
- 4, /* single precision (s) */
- 8 /* double precision (d) */
-};
-
-static inline void
-mem2float_extended (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldfe(6, init);
- ia64_stop();
- ia64_stf_spill(final, 6);
-}
-
-static inline void
-mem2float_integer (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldf8(6, init);
- ia64_stop();
- ia64_stf_spill(final, 6);
-}
-
-static inline void
-mem2float_single (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldfs(6, init);
- ia64_stop();
- ia64_stf_spill(final, 6);
-}
-
-static inline void
-mem2float_double (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldfd(6, init);
- ia64_stop();
- ia64_stf_spill(final, 6);
-}
-
-static inline void
-float2mem_extended (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldf_fill(6, init);
- ia64_stop();
- ia64_stfe(final, 6);
-}
-
-static inline void
-float2mem_integer (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldf_fill(6, init);
- ia64_stop();
- ia64_stf8(final, 6);
-}
-
-static inline void
-float2mem_single (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldf_fill(6, init);
- ia64_stop();
- ia64_stfs(final, 6);
-}
-
-static inline void
-float2mem_double (struct ia64_fpreg *init, struct ia64_fpreg *final)
-{
- ia64_ldf_fill(6, init);
- ia64_stop();
- ia64_stfd(final, 6);
-}
-
-static int
-emulate_load_floatpair (unsigned long ifa, load_store_t ld, struct pt_regs *regs, bool kernel_mode)
-{
- struct ia64_fpreg fpr_init[2];
- struct ia64_fpreg fpr_final[2];
- unsigned long len = float_fsz[ld.x6_sz];
-
- /*
- * fr0 & fr1 don't need to be checked because Illegal Instruction faults have
- * higher priority than unaligned faults.
- *
- * r0 cannot be found as the base as it would never generate an unaligned
- * reference.
- */
-
- /*
- * make sure we get clean buffers
- */
- memset(&fpr_init, 0, sizeof(fpr_init));
- memset(&fpr_final, 0, sizeof(fpr_final));
-
- /*
- * ldfpX.a: we don't try to emulate anything but we must
- * invalidate the ALAT entry and execute updates, if any.
- */
- if (ld.x6_op != 0x2) {
- /*
- * This assumes little-endian byte-order. Note that there is no "ldfpe"
- * instruction:
- */
- if (emulate_load(&fpr_init[0], ifa, len, kernel_mode)
- || emulate_load(&fpr_init[1], (ifa + len), len, kernel_mode))
- return -1;
-
- DPRINT("ld.r1=%d ld.imm=%d x6_sz=%d\n", ld.r1, ld.imm, ld.x6_sz);
- DDUMP("frp_init =", &fpr_init, 2*len);
- /*
- * XXX fixme
- * Could optimize inlines by using ldfpX & 2 spills
- */
- switch( ld.x6_sz ) {
- case 0:
- mem2float_extended(&fpr_init[0], &fpr_final[0]);
- mem2float_extended(&fpr_init[1], &fpr_final[1]);
- break;
- case 1:
- mem2float_integer(&fpr_init[0], &fpr_final[0]);
- mem2float_integer(&fpr_init[1], &fpr_final[1]);
- break;
- case 2:
- mem2float_single(&fpr_init[0], &fpr_final[0]);
- mem2float_single(&fpr_init[1], &fpr_final[1]);
- break;
- case 3:
- mem2float_double(&fpr_init[0], &fpr_final[0]);
- mem2float_double(&fpr_init[1], &fpr_final[1]);
- break;
- }
- DDUMP("fpr_final =", &fpr_final, 2*len);
- /*
- * XXX fixme
- *
- * A possible optimization would be to drop fpr_final and directly
- * use the storage from the saved context i.e., the actual final
- * destination (pt_regs, switch_stack or thread structure).
- */
- setfpreg(ld.r1, &fpr_final[0], regs);
- setfpreg(ld.imm, &fpr_final[1], regs);
- }
-
- /*
- * Check for updates: only immediate updates are available for this
- * instruction.
- */
- if (ld.m) {
- /*
- * the immediate is implicit given the ldsz of the operation:
- * single: 8 (2x4) and for all others it's 16 (2x8)
- */
- ifa += len<<1;
-
- /*
- * IMPORTANT:
- * the fact that we force the NaT of r3 to zero is ONLY valid
- * as long as we don't come here with a ldfpX.s.
- * For this reason we keep this sanity check
- */
- if (ld.x6_op == 1 || ld.x6_op == 3)
- printk(KERN_ERR "%s: register update on speculative load pair, error\n",
- __func__);
-
- setreg(ld.r3, ifa, 0, regs);
- }
-
- /*
- * Invalidate ALAT entries, if any, for both registers.
- */
- if (ld.x6_op == 0x2) {
- invala_fr(ld.r1);
- invala_fr(ld.imm);
- }
- return 0;
-}
-
-
-static int
-emulate_load_float (unsigned long ifa, load_store_t ld, struct pt_regs *regs,
- bool kernel_mode)
-{
- struct ia64_fpreg fpr_init;
- struct ia64_fpreg fpr_final;
- unsigned long len = float_fsz[ld.x6_sz];
-
- /*
- * fr0 & fr1 don't need to be checked because Illegal Instruction
- * faults have higher priority than unaligned faults.
- *
- * r0 cannot be found as the base as it would never generate an
- * unaligned reference.
- */
-
- /*
- * make sure we get clean buffers
- */
- memset(&fpr_init,0, sizeof(fpr_init));
- memset(&fpr_final,0, sizeof(fpr_final));
-
- /*
- * ldfX.a we don't try to emulate anything but we must
- * invalidate the ALAT entry.
- * See comments in ldX for descriptions on how the various loads are handled.
- */
- if (ld.x6_op != 0x2) {
- if (emulate_load(&fpr_init, ifa, len, kernel_mode))
- return -1;
-
- DPRINT("ld.r1=%d x6_sz=%d\n", ld.r1, ld.x6_sz);
- DDUMP("fpr_init =", &fpr_init, len);
- /*
- * we only do something for x6_op={0,8,9}
- */
- switch( ld.x6_sz ) {
- case 0:
- mem2float_extended(&fpr_init, &fpr_final);
- break;
- case 1:
- mem2float_integer(&fpr_init, &fpr_final);
- break;
- case 2:
- mem2float_single(&fpr_init, &fpr_final);
- break;
- case 3:
- mem2float_double(&fpr_init, &fpr_final);
- break;
- }
- DDUMP("fpr_final =", &fpr_final, len);
- /*
- * XXX fixme
- *
- * A possible optimization would be to drop fpr_final and directly
- * use the storage from the saved context i.e., the actual final
- * destination (pt_regs, switch_stack or thread structure).
- */
- setfpreg(ld.r1, &fpr_final, regs);
- }
-
- /*
- * check for updates on any loads
- */
- if (ld.op == 0x7 || ld.m)
- emulate_load_updates(ld.op == 0x7 ? UPD_IMMEDIATE: UPD_REG, ld, regs, ifa);
-
- /*
- * invalidate ALAT entry in case of advanced floating point loads
- */
- if (ld.x6_op == 0x2)
- invala_fr(ld.r1);
-
- return 0;
-}
-
-
-static int
-emulate_store_float (unsigned long ifa, load_store_t ld, struct pt_regs *regs,
- bool kernel_mode)
-{
- struct ia64_fpreg fpr_init;
- struct ia64_fpreg fpr_final;
- unsigned long len = float_fsz[ld.x6_sz];
-
- /*
- * make sure we get clean buffers
- */
- memset(&fpr_init,0, sizeof(fpr_init));
- memset(&fpr_final,0, sizeof(fpr_final));
-
- /*
- * if we get to this handler, Nat bits on both r3 and r2 have already
- * been checked. so we don't need to do it
- *
- * extract the value to be stored
- */
- getfpreg(ld.imm, &fpr_init, regs);
- /*
- * during this step, we extract the spilled registers from the saved
- * context i.e., we refill. Then we store (no spill) to temporary
- * aligned location
- */
- switch( ld.x6_sz ) {
- case 0:
- float2mem_extended(&fpr_init, &fpr_final);
- break;
- case 1:
- float2mem_integer(&fpr_init, &fpr_final);
- break;
- case 2:
- float2mem_single(&fpr_init, &fpr_final);
- break;
- case 3:
- float2mem_double(&fpr_init, &fpr_final);
- break;
- }
- DPRINT("ld.r1=%d x6_sz=%d\n", ld.r1, ld.x6_sz);
- DDUMP("fpr_init =", &fpr_init, len);
- DDUMP("fpr_final =", &fpr_final, len);
-
- if (emulate_store(ifa, &fpr_final, len, kernel_mode))
- return -1;
-
- /*
- * stfX [r3]=r2,imm(9)
- *
- * NOTE:
- * ld.r3 can never be r0, because r0 would not generate an
- * unaligned access.
- */
- if (ld.op == 0x7) {
- unsigned long imm;
-
- /*
- * form imm9: [12:6] contain first 7bits
- */
- imm = ld.x << 7 | ld.r1;
- /*
- * sign extend (8bits) if m set
- */
- if (ld.m)
- imm |= SIGN_EXT9;
- /*
- * ifa == r3 (NaT is necessarily cleared)
- */
- ifa += imm;
-
- DPRINT("imm=%lx r3=%lx\n", imm, ifa);
-
- setreg(ld.r3, ifa, 0, regs);
- }
- /*
- * we don't have alat_invalidate_multiple() so we need
- * to do the complete flush :-<<
- */
- ia64_invala();
-
- return 0;
-}
-
-/*
- * Make sure we log the unaligned access, so that user/sysadmin can notice it and
- * eventually fix the program. However, we don't want to do that for every access so we
- * pace it with jiffies.
- */
-static DEFINE_RATELIMIT_STATE(logging_rate_limit, 5 * HZ, 5);
-
-void
-ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)
-{
- struct ia64_psr *ipsr = ia64_psr(regs);
- unsigned long bundle[2];
- unsigned long opcode;
- const struct exception_table_entry *eh = NULL;
- union {
- unsigned long l;
- load_store_t insn;
- } u;
- int ret = -1;
- bool kernel_mode = false;
-
- if (ia64_psr(regs)->be) {
- /* we don't support big-endian accesses */
- if (die_if_kernel("big-endian unaligned accesses are not supported", regs, 0))
- return;
- goto force_sigbus;
- }
-
- /*
- * Treat kernel accesses for which there is an exception handler entry the same as
- * user-level unaligned accesses. Otherwise, a clever program could trick this
- * handler into reading an arbitrary kernel addresses...
- */
- if (!user_mode(regs))
- eh = search_exception_tables(regs->cr_iip + ia64_psr(regs)->ri);
- if (user_mode(regs) || eh) {
- if ((current->thread.flags & IA64_THREAD_UAC_SIGBUS) != 0)
- goto force_sigbus;
-
- if (!no_unaligned_warning &&
- !(current->thread.flags & IA64_THREAD_UAC_NOPRINT) &&
- __ratelimit(&logging_rate_limit))
- {
- char buf[200]; /* comm[] is at most 16 bytes... */
- size_t len;
-
- len = sprintf(buf, "%s(%d): unaligned access to 0x%016lx, "
- "ip=0x%016lx\n\r", current->comm,
- task_pid_nr(current),
- ifa, regs->cr_iip + ipsr->ri);
- /*
- * Don't call tty_write_message() if we're in the kernel; we might
- * be holding locks...
- */
- if (user_mode(regs)) {
- struct tty_struct *tty = get_current_tty();
- tty_write_message(tty, buf);
- tty_kref_put(tty);
- }
- buf[len-1] = '\0'; /* drop '\r' */
- /* watch for command names containing %s */
- printk(KERN_WARNING "%s", buf);
- } else {
- if (no_unaligned_warning) {
- printk_once(KERN_WARNING "%s(%d) encountered an "
- "unaligned exception which required\n"
- "kernel assistance, which degrades "
- "the performance of the application.\n"
- "Unaligned exception warnings have "
- "been disabled by the system "
- "administrator\n"
- "echo 0 > /proc/sys/kernel/ignore-"
- "unaligned-usertrap to re-enable\n",
- current->comm, task_pid_nr(current));
- }
- }
- } else {
- if (__ratelimit(&logging_rate_limit)) {
- printk(KERN_WARNING "kernel unaligned access to 0x%016lx, ip=0x%016lx\n",
- ifa, regs->cr_iip + ipsr->ri);
- if (unaligned_dump_stack)
- dump_stack();
- }
- kernel_mode = true;
- }
-
- DPRINT("iip=%lx ifa=%lx isr=%lx (ei=%d, sp=%d)\n",
- regs->cr_iip, ifa, regs->cr_ipsr, ipsr->ri, ipsr->it);
-
- if (emulate_load(bundle, regs->cr_iip, 16, kernel_mode))
- goto failure;
-
- /*
- * extract the instruction from the bundle given the slot number
- */
- switch (ipsr->ri) {
- default:
- case 0: u.l = (bundle[0] >> 5); break;
- case 1: u.l = (bundle[0] >> 46) | (bundle[1] << 18); break;
- case 2: u.l = (bundle[1] >> 23); break;
- }
- opcode = (u.l >> IA64_OPCODE_SHIFT) & IA64_OPCODE_MASK;
-
- DPRINT("opcode=%lx ld.qp=%d ld.r1=%d ld.imm=%d ld.r3=%d ld.x=%d ld.hint=%d "
- "ld.x6=0x%x ld.m=%d ld.op=%d\n", opcode, u.insn.qp, u.insn.r1, u.insn.imm,
- u.insn.r3, u.insn.x, u.insn.hint, u.insn.x6_sz, u.insn.m, u.insn.op);
-
- /*
- * IMPORTANT:
- * Notice that the switch statement DOES not cover all possible instructions
- * that DO generate unaligned references. This is made on purpose because for some
- * instructions it DOES NOT make sense to try and emulate the access. Sometimes it
- * is WRONG to try and emulate. Here is a list of instruction we don't emulate i.e.,
- * the program will get a signal and die:
- *
- * load/store:
- * - ldX.spill
- * - stX.spill
- * Reason: RNATs are based on addresses
- * - ld16
- * - st16
- * Reason: ld16 and st16 are supposed to occur in a single
- * memory op
- *
- * synchronization:
- * - cmpxchg
- * - fetchadd
- * - xchg
- * Reason: ATOMIC operations cannot be emulated properly using multiple
- * instructions.
- *
- * speculative loads:
- * - ldX.sZ
- * Reason: side effects, code must be ready to deal with failure so simpler
- * to let the load fail.
- * ---------------------------------------------------------------------------------
- * XXX fixme
- *
- * I would like to get rid of this switch case and do something
- * more elegant.
- */
- switch (opcode) {
- case LDS_OP:
- case LDSA_OP:
- if (u.insn.x)
- /* oops, really a semaphore op (cmpxchg, etc) */
- goto failure;
- fallthrough;
- case LDS_IMM_OP:
- case LDSA_IMM_OP:
- case LDFS_OP:
- case LDFSA_OP:
- case LDFS_IMM_OP:
- /*
- * The instruction will be retried with deferred exceptions turned on, and
- * we should get Nat bit installed
- *
- * IMPORTANT: When PSR_ED is set, the register & immediate update forms
- * are actually executed even though the operation failed. So we don't
- * need to take care of this.
- */
- DPRINT("forcing PSR_ED\n");
- regs->cr_ipsr |= IA64_PSR_ED;
- goto done;
-
- case LD_OP:
- case LDA_OP:
- case LDBIAS_OP:
- case LDACQ_OP:
- case LDCCLR_OP:
- case LDCNC_OP:
- case LDCCLRACQ_OP:
- if (u.insn.x)
- /* oops, really a semaphore op (cmpxchg, etc) */
- goto failure;
- fallthrough;
- case LD_IMM_OP:
- case LDA_IMM_OP:
- case LDBIAS_IMM_OP:
- case LDACQ_IMM_OP:
- case LDCCLR_IMM_OP:
- case LDCNC_IMM_OP:
- case LDCCLRACQ_IMM_OP:
- ret = emulate_load_int(ifa, u.insn, regs, kernel_mode);
- break;
-
- case ST_OP:
- case STREL_OP:
- if (u.insn.x)
- /* oops, really a semaphore op (cmpxchg, etc) */
- goto failure;
- fallthrough;
- case ST_IMM_OP:
- case STREL_IMM_OP:
- ret = emulate_store_int(ifa, u.insn, regs, kernel_mode);
- break;
-
- case LDF_OP:
- case LDFA_OP:
- case LDFCCLR_OP:
- case LDFCNC_OP:
- if (u.insn.x)
- ret = emulate_load_floatpair(ifa, u.insn, regs, kernel_mode);
- else
- ret = emulate_load_float(ifa, u.insn, regs, kernel_mode);
- break;
-
- case LDF_IMM_OP:
- case LDFA_IMM_OP:
- case LDFCCLR_IMM_OP:
- case LDFCNC_IMM_OP:
- ret = emulate_load_float(ifa, u.insn, regs, kernel_mode);
- break;
-
- case STF_OP:
- case STF_IMM_OP:
- ret = emulate_store_float(ifa, u.insn, regs, kernel_mode);
- break;
-
- default:
- goto failure;
- }
- DPRINT("ret=%d\n", ret);
- if (ret)
- goto failure;
-
- if (ipsr->ri == 2)
- /*
- * given today's architecture this case is not likely to happen because a
- * memory access instruction (M) can never be in the last slot of a
- * bundle. But let's keep it for now.
- */
- regs->cr_iip += 16;
- ipsr->ri = (ipsr->ri + 1) & 0x3;
-
- DPRINT("ipsr->ri=%d iip=%lx\n", ipsr->ri, regs->cr_iip);
- done:
- return;
-
- failure:
- /* something went wrong... */
- if (!user_mode(regs)) {
- if (eh) {
- ia64_handle_exception(regs, eh);
- goto done;
- }
- if (die_if_kernel("error during unaligned kernel access\n", regs, ret))
- return;
- /* NOT_REACHED */
- }
- force_sigbus:
- force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) ifa,
- 0, 0, 0);
- goto done;
-}