forked from Minki/linux
9ff4cfb3fc
From: Christian Borntraeger <borntraeger@de.ibm.com> This patch fixes the sie exit on interrupts. The low level interrupt handler returns to the PSW address in pt_regs and not to the PSW address in the lowcore. Without this fix a cpu bound guest might never leave guest state since the host interrupt handler would blindly return to the SIE instruction, even on need_resched and friends. Cc: stable@kernel.org Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
97 lines
2.3 KiB
ArmAsm
97 lines
2.3 KiB
ArmAsm
/*
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* sie64a.S - low level sie call
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*
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* Copyright IBM Corp. 2008,2010
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License (version 2 only)
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* as published by the Free Software Foundation.
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*
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* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
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* Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
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*/
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#include <linux/errno.h>
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#include <asm/asm-offsets.h>
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#include <asm/setup.h>
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#include <asm/asm-offsets.h>
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#include <asm/ptrace.h>
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#include <asm/thread_info.h>
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_TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING)
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/*
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* offsets into stackframe
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* SP_ = offsets into stack sie64 is called with
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* SPI_ = offsets into irq stack
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*/
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SP_GREGS = __SF_EMPTY
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SP_HOOK = __SF_EMPTY+8
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SP_GPP = __SF_EMPTY+16
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SPI_PSW = STACK_FRAME_OVERHEAD + __PT_PSW
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.macro SPP newpp
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tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_SPP
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jz 0f
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.insn s,0xb2800000,\newpp
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0:
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.endm
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sie_irq_handler:
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SPP __LC_CMF_HPP # set host id
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larl %r2,sie_inst
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clg %r2,SPI_PSW+8(0,%r15) # intercepted sie
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jne 1f
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xc __LC_SIE_HOOK(8),__LC_SIE_HOOK
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lg %r2,__LC_THREAD_INFO # pointer thread_info struct
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tm __TI_flags+7(%r2),_TIF_EXIT_SIE
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jz 0f
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larl %r2,sie_exit # work pending, leave sie
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stg %r2,SPI_PSW+8(0,%r15)
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br %r14
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0: larl %r2,sie_reenter # re-enter with guest id
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stg %r2,SPI_PSW+8(0,%r15)
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1: br %r14
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/*
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* sie64a calling convention:
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* %r2 pointer to sie control block
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* %r3 guest register save area
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*/
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.globl sie64a
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sie64a:
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stg %r3,SP_GREGS(%r15) # save guest register save area
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stmg %r6,%r14,__SF_GPRS(%r15) # save registers on entry
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lgr %r14,%r2 # pointer to sie control block
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larl %r5,sie_irq_handler
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stg %r2,SP_GPP(%r15)
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stg %r5,SP_HOOK(%r15) # save hook target
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lmg %r0,%r13,0(%r3) # load guest gprs 0-13
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sie_reenter:
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mvc __LC_SIE_HOOK(8),SP_HOOK(%r15)
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SPP SP_GPP(%r15) # set guest id
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sie_inst:
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sie 0(%r14)
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xc __LC_SIE_HOOK(8),__LC_SIE_HOOK
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SPP __LC_CMF_HPP # set host id
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sie_exit:
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lg %r14,SP_GREGS(%r15)
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stmg %r0,%r13,0(%r14) # save guest gprs 0-13
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lghi %r2,0
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lmg %r6,%r14,__SF_GPRS(%r15)
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br %r14
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sie_err:
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xc __LC_SIE_HOOK(8),__LC_SIE_HOOK
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SPP __LC_CMF_HPP # set host id
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lg %r14,SP_GREGS(%r15)
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stmg %r0,%r13,0(%r14) # save guest gprs 0-13
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lghi %r2,-EFAULT
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lmg %r6,%r14,__SF_GPRS(%r15)
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br %r14
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.section __ex_table,"a"
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.quad sie_inst,sie_err
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.previous
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