cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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etrap_64.S (7235B)


      1/* SPDX-License-Identifier: GPL-2.0 */
      2/*
      3 * etrap.S: Preparing for entry into the kernel on Sparc V9.
      4 *
      5 * Copyright (C) 1996, 1997 David S. Miller (davem@caip.rutgers.edu)
      6 * Copyright (C) 1997, 1998, 1999 Jakub Jelinek (jj@ultra.linux.cz)
      7 */
      8
      9
     10#include <asm/asi.h>
     11#include <asm/pstate.h>
     12#include <asm/ptrace.h>
     13#include <asm/page.h>
     14#include <asm/spitfire.h>
     15#include <asm/head.h>
     16#include <asm/processor.h>
     17#include <asm/mmu.h>
     18
     19#define		TASK_REGOFF		(THREAD_SIZE-TRACEREG_SZ-STACKFRAME_SZ)
     20#define		ETRAP_PSTATE1		(PSTATE_TSO | PSTATE_PRIV)
     21#define		ETRAP_PSTATE2		\
     22		(PSTATE_TSO | PSTATE_PEF | PSTATE_PRIV | PSTATE_IE)
     23
     24/*
     25 * On entry, %g7 is return address - 0x4.
     26 * %g4 and %g5 will be preserved %l4 and %l5 respectively.
     27 */
     28
     29		.text		
     30		.align	64
     31		.globl	etrap_syscall, etrap, etrap_irq, etraptl1
     32etrap:		rdpr	%pil, %g2
     33etrap_irq:	clr	%g3
     34etrap_syscall:	TRAP_LOAD_THREAD_REG(%g6, %g1)
     35		rdpr	%tstate, %g1
     36		or	%g1, %g3, %g1
     37		sllx	%g2, 20, %g3
     38		andcc	%g1, TSTATE_PRIV, %g0
     39		or	%g1, %g3, %g1
     40		bne,pn	%xcc, 1f
     41		 sub	%sp, STACKFRAME_SZ+TRACEREG_SZ-STACK_BIAS, %g2
     42661:		wrpr	%g0, 7, %cleanwin
     43		.section .fast_win_ctrl_1insn_patch, "ax"
     44		.word	661b
     45		.word	0x85880000	! allclean
     46		.previous
     47
     48		sethi	%hi(TASK_REGOFF), %g2
     49		sethi	%hi(TSTATE_PEF), %g3
     50		or	%g2, %lo(TASK_REGOFF), %g2
     51		and	%g1, %g3, %g3
     52		brnz,pn	%g3, 1f
     53		 add	%g6, %g2, %g2
     54		wr	%g0, 0, %fprs
     551:		rdpr	%tpc, %g3
     56
     57		stx	%g1, [%g2 + STACKFRAME_SZ + PT_V9_TSTATE]
     58		rdpr	%tnpc, %g1
     59		stx	%g3, [%g2 + STACKFRAME_SZ + PT_V9_TPC]
     60		rd	%y, %g3
     61		stx	%g1, [%g2 + STACKFRAME_SZ + PT_V9_TNPC]
     62		rdpr	%tt, %g1
     63		st	%g3, [%g2 + STACKFRAME_SZ + PT_V9_Y]
     64		sethi	%hi(PT_REGS_MAGIC), %g3
     65		or	%g3, %g1, %g1
     66		st	%g1, [%g2 + STACKFRAME_SZ + PT_V9_MAGIC]
     67
     68		rdpr	%cansave, %g1
     69		brnz,pt %g1, etrap_save
     70		 nop
     71
     72		rdpr	%cwp, %g1
     73		add	%g1, 2, %g1
     74		wrpr	%g1, %cwp
     75		be,pt	%xcc, etrap_user_spill
     76		 mov	ASI_AIUP, %g3
     77
     78		rdpr	%otherwin, %g3
     79		brz	%g3, etrap_kernel_spill
     80		 mov	ASI_AIUS, %g3
     81
     82etrap_user_spill:
     83
     84		wr	%g3, 0x0, %asi
     85		ldx	[%g6 + TI_FLAGS], %g3
     86		and	%g3, _TIF_32BIT, %g3
     87		brnz,pt	%g3, etrap_user_spill_32bit
     88		 nop
     89		ba,a,pt	%xcc, etrap_user_spill_64bit
     90
     91etrap_save:	save	%g2, -STACK_BIAS, %sp
     92		mov	%g6, %l6
     93
     94		bne,pn	%xcc, 3f
     95		 mov	PRIMARY_CONTEXT, %l4
     96661:		rdpr	%canrestore, %g3
     97		.section .fast_win_ctrl_1insn_patch, "ax"
     98		.word	661b
     99		nop
    100		.previous
    101
    102		rdpr	%wstate, %g2
    103661:		wrpr	%g0, 0, %canrestore
    104		.section .fast_win_ctrl_1insn_patch, "ax"
    105		.word	661b
    106		nop
    107		.previous
    108		sll	%g2, 3, %g2
    109
    110		/* Set TI_SYS_FPDEPTH to 1 and clear TI_SYS_NOERROR.  */
    111		mov	1, %l5
    112		sth	%l5, [%l6 + TI_SYS_NOERROR]
    113
    114661:		wrpr	%g3, 0, %otherwin
    115		.section .fast_win_ctrl_1insn_patch, "ax"
    116		.word	661b
    117		.word	0x87880000	! otherw
    118		.previous
    119
    120		wrpr	%g2, 0, %wstate
    121		sethi	%hi(sparc64_kern_pri_context), %g2
    122		ldx	[%g2 + %lo(sparc64_kern_pri_context)], %g3
    123
    124661:		stxa	%g3, [%l4] ASI_DMMU
    125		.section .sun4v_1insn_patch, "ax"
    126		.word	661b
    127		stxa	%g3, [%l4] ASI_MMU
    128		.previous
    129
    130		sethi	%hi(KERNBASE), %l4
    131		flush	%l4
    132		mov	ASI_AIUS, %l7
    1332:		mov	%g4, %l4
    134		mov	%g5, %l5
    135		add	%g7, 4, %l2
    136
    137		/* Go to trap time globals so we can save them.  */
    138661:		wrpr	%g0, ETRAP_PSTATE1, %pstate
    139		.section .sun4v_1insn_patch, "ax"
    140		.word	661b
    141		SET_GL(0)
    142		.previous
    143
    144		stx	%g1, [%sp + PTREGS_OFF + PT_V9_G1]
    145		stx	%g2, [%sp + PTREGS_OFF + PT_V9_G2]
    146		sllx	%l7, 24, %l7
    147		stx	%g3, [%sp + PTREGS_OFF + PT_V9_G3]
    148		rdpr	%cwp, %l0
    149		stx	%g4, [%sp + PTREGS_OFF + PT_V9_G4]
    150		stx	%g5, [%sp + PTREGS_OFF + PT_V9_G5]
    151		stx	%g6, [%sp + PTREGS_OFF + PT_V9_G6]
    152		stx	%g7, [%sp + PTREGS_OFF + PT_V9_G7]
    153		or	%l7, %l0, %l7
    154661:		sethi	%hi(TSTATE_TSO | TSTATE_PEF), %l0
    155		/* If userspace is using ADI, it could potentially pass
    156		 * a pointer with version tag embedded in it. To maintain
    157		 * the ADI security, we must enable PSTATE.mcde. Userspace
    158		 * would have already set TTE.mcd in an earlier call to
    159		 * kernel and set the version tag for the address being
    160		 * dereferenced. Setting PSTATE.mcde would ensure any
    161		 * access to userspace data through a system call honors
    162		 * ADI and does not allow a rogue app to bypass ADI by
    163		 * using system calls. Setting PSTATE.mcde only affects
    164		 * accesses to virtual addresses that have TTE.mcd set.
    165		 * Set PMCDPER to ensure any exceptions caused by ADI
    166		 * version tag mismatch are exposed before system call
    167		 * returns to userspace. Setting PMCDPER affects only
    168		 * writes to virtual addresses that have TTE.mcd set and
    169		 * have a version tag set as well.
    170		 */
    171		.section .sun_m7_1insn_patch, "ax"
    172		.word	661b
    173		sethi	%hi(TSTATE_TSO | TSTATE_PEF | TSTATE_MCDE), %l0
    174		.previous
    175661:		nop
    176		.section .sun_m7_1insn_patch, "ax"
    177		.word	661b
    178		.word 0xaf902001	/* wrpr %g0, 1, %pmcdper */
    179		.previous
    180		or	%l7, %l0, %l7
    181		wrpr	%l2, %tnpc
    182		wrpr	%l7, (TSTATE_PRIV | TSTATE_IE), %tstate
    183		stx	%i0, [%sp + PTREGS_OFF + PT_V9_I0]
    184		stx	%i1, [%sp + PTREGS_OFF + PT_V9_I1]
    185		stx	%i2, [%sp + PTREGS_OFF + PT_V9_I2]
    186		stx	%i3, [%sp + PTREGS_OFF + PT_V9_I3]
    187		stx	%i4, [%sp + PTREGS_OFF + PT_V9_I4]
    188		stx	%i5, [%sp + PTREGS_OFF + PT_V9_I5]
    189		stx	%i6, [%sp + PTREGS_OFF + PT_V9_I6]
    190		mov	%l6, %g6
    191		stx	%i7, [%sp + PTREGS_OFF + PT_V9_I7]
    192		LOAD_PER_CPU_BASE(%g5, %g6, %g4, %g3, %l1)
    193		ldx	[%g6 + TI_TASK], %g4
    194		done
    195
    1963:		mov	ASI_P, %l7
    197		ldub	[%l6 + TI_FPDEPTH], %l5
    198		add	%l6, TI_FPSAVED + 1, %l4
    199		srl	%l5, 1, %l3
    200		add	%l5, 2, %l5
    201
    202		/* Set TI_SYS_FPDEPTH to %l5 and clear TI_SYS_NOERROR.  */
    203		sth	%l5, [%l6 + TI_SYS_NOERROR]
    204		ba,pt	%xcc, 2b
    205		 stb	%g0, [%l4 + %l3]
    206		nop
    207
    208etraptl1:	/* Save tstate/tpc/tnpc of TL 1-->4 and the tl register itself.
    209		 * We place this right after pt_regs on the trap stack.
    210		 * The layout is:
    211		 *	0x00	TL1's TSTATE
    212		 *	0x08	TL1's TPC
    213		 *	0x10	TL1's TNPC
    214		 *	0x18	TL1's TT
    215		 *	 ...
    216		 *	0x58	TL4's TT
    217		 *	0x60	TL
    218		 */
    219		TRAP_LOAD_THREAD_REG(%g6, %g1)
    220		sub	%sp, ((4 * 8) * 4) + 8, %g2
    221		rdpr	%tl, %g1
    222
    223		wrpr	%g0, 1, %tl
    224		rdpr	%tstate, %g3
    225		stx	%g3, [%g2 + STACK_BIAS + 0x00]
    226		rdpr	%tpc, %g3
    227		stx	%g3, [%g2 + STACK_BIAS + 0x08]
    228		rdpr	%tnpc, %g3
    229		stx	%g3, [%g2 + STACK_BIAS + 0x10]
    230		rdpr	%tt, %g3
    231		stx	%g3, [%g2 + STACK_BIAS + 0x18]
    232
    233		wrpr	%g0, 2, %tl
    234		rdpr	%tstate, %g3
    235		stx	%g3, [%g2 + STACK_BIAS + 0x20]
    236		rdpr	%tpc, %g3
    237		stx	%g3, [%g2 + STACK_BIAS + 0x28]
    238		rdpr	%tnpc, %g3
    239		stx	%g3, [%g2 + STACK_BIAS + 0x30]
    240		rdpr	%tt, %g3
    241		stx	%g3, [%g2 + STACK_BIAS + 0x38]
    242
    243		sethi	%hi(is_sun4v), %g3
    244		lduw	[%g3 + %lo(is_sun4v)], %g3
    245		brnz,pn	%g3, finish_tl1_capture
    246		 nop
    247
    248		wrpr	%g0, 3, %tl
    249		rdpr	%tstate, %g3
    250		stx	%g3, [%g2 + STACK_BIAS + 0x40]
    251		rdpr	%tpc, %g3
    252		stx	%g3, [%g2 + STACK_BIAS + 0x48]
    253		rdpr	%tnpc, %g3
    254		stx	%g3, [%g2 + STACK_BIAS + 0x50]
    255		rdpr	%tt, %g3
    256		stx	%g3, [%g2 + STACK_BIAS + 0x58]
    257
    258		wrpr	%g0, 4, %tl
    259		rdpr	%tstate, %g3
    260		stx	%g3, [%g2 + STACK_BIAS + 0x60]
    261		rdpr	%tpc, %g3
    262		stx	%g3, [%g2 + STACK_BIAS + 0x68]
    263		rdpr	%tnpc, %g3
    264		stx	%g3, [%g2 + STACK_BIAS + 0x70]
    265		rdpr	%tt, %g3
    266		stx	%g3, [%g2 + STACK_BIAS + 0x78]
    267
    268		stx	%g1, [%g2 + STACK_BIAS + 0x80]
    269
    270finish_tl1_capture:
    271		wrpr	%g0, 1, %tl
    272661:		nop
    273		.section .sun4v_1insn_patch, "ax"
    274		.word	661b
    275		SET_GL(1)
    276		.previous
    277
    278		rdpr	%tstate, %g1
    279		sub	%g2, STACKFRAME_SZ + TRACEREG_SZ - STACK_BIAS, %g2
    280		ba,pt	%xcc, 1b
    281		 andcc	%g1, TSTATE_PRIV, %g0
    282
    283#undef TASK_REGOFF
    284#undef ETRAP_PSTATE1