162 lines
3.4 KiB
C
162 lines
3.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Common helper functions for kprobes and uprobes
|
|
*
|
|
* Copyright IBM Corp. 2014
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <asm/kprobes.h>
|
|
#include <asm/dis.h>
|
|
|
|
int probe_is_prohibited_opcode(u16 *insn)
|
|
{
|
|
if (!is_known_insn((unsigned char *)insn))
|
|
return -EINVAL;
|
|
switch (insn[0] >> 8) {
|
|
case 0x0c: /* bassm */
|
|
case 0x0b: /* bsm */
|
|
case 0x83: /* diag */
|
|
case 0x44: /* ex */
|
|
case 0xac: /* stnsm */
|
|
case 0xad: /* stosm */
|
|
return -EINVAL;
|
|
case 0xc6:
|
|
switch (insn[0] & 0x0f) {
|
|
case 0x00: /* exrl */
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
switch (insn[0]) {
|
|
case 0x0101: /* pr */
|
|
case 0xb25a: /* bsa */
|
|
case 0xb240: /* bakr */
|
|
case 0xb258: /* bsg */
|
|
case 0xb218: /* pc */
|
|
case 0xb228: /* pt */
|
|
case 0xb98d: /* epsw */
|
|
case 0xe560: /* tbegin */
|
|
case 0xe561: /* tbeginc */
|
|
case 0xb2f8: /* tend */
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int probe_get_fixup_type(u16 *insn)
|
|
{
|
|
/* default fixup method */
|
|
int fixup = FIXUP_PSW_NORMAL;
|
|
|
|
switch (insn[0] >> 8) {
|
|
case 0x05: /* balr */
|
|
case 0x0d: /* basr */
|
|
fixup = FIXUP_RETURN_REGISTER;
|
|
/* if r2 = 0, no branch will be taken */
|
|
if ((insn[0] & 0x0f) == 0)
|
|
fixup |= FIXUP_BRANCH_NOT_TAKEN;
|
|
break;
|
|
case 0x06: /* bctr */
|
|
case 0x07: /* bcr */
|
|
fixup = FIXUP_BRANCH_NOT_TAKEN;
|
|
break;
|
|
case 0x45: /* bal */
|
|
case 0x4d: /* bas */
|
|
fixup = FIXUP_RETURN_REGISTER;
|
|
break;
|
|
case 0x47: /* bc */
|
|
case 0x46: /* bct */
|
|
case 0x86: /* bxh */
|
|
case 0x87: /* bxle */
|
|
fixup = FIXUP_BRANCH_NOT_TAKEN;
|
|
break;
|
|
case 0x82: /* lpsw */
|
|
fixup = FIXUP_NOT_REQUIRED;
|
|
break;
|
|
case 0xb2: /* lpswe */
|
|
if ((insn[0] & 0xff) == 0xb2)
|
|
fixup = FIXUP_NOT_REQUIRED;
|
|
break;
|
|
case 0xa7: /* bras */
|
|
if ((insn[0] & 0x0f) == 0x05)
|
|
fixup |= FIXUP_RETURN_REGISTER;
|
|
break;
|
|
case 0xc0:
|
|
if ((insn[0] & 0x0f) == 0x05) /* brasl */
|
|
fixup |= FIXUP_RETURN_REGISTER;
|
|
break;
|
|
case 0xeb:
|
|
switch (insn[2] & 0xff) {
|
|
case 0x44: /* bxhg */
|
|
case 0x45: /* bxleg */
|
|
fixup = FIXUP_BRANCH_NOT_TAKEN;
|
|
break;
|
|
}
|
|
break;
|
|
case 0xe3: /* bctg */
|
|
if ((insn[2] & 0xff) == 0x46)
|
|
fixup = FIXUP_BRANCH_NOT_TAKEN;
|
|
break;
|
|
case 0xec:
|
|
switch (insn[2] & 0xff) {
|
|
case 0xe5: /* clgrb */
|
|
case 0xe6: /* cgrb */
|
|
case 0xf6: /* crb */
|
|
case 0xf7: /* clrb */
|
|
case 0xfc: /* cgib */
|
|
case 0xfd: /* cglib */
|
|
case 0xfe: /* cib */
|
|
case 0xff: /* clib */
|
|
fixup = FIXUP_BRANCH_NOT_TAKEN;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
return fixup;
|
|
}
|
|
|
|
int probe_is_insn_relative_long(u16 *insn)
|
|
{
|
|
/* Check if we have a RIL-b or RIL-c format instruction which
|
|
* we need to modify in order to avoid instruction emulation. */
|
|
switch (insn[0] >> 8) {
|
|
case 0xc0:
|
|
if ((insn[0] & 0x0f) == 0x00) /* larl */
|
|
return true;
|
|
break;
|
|
case 0xc4:
|
|
switch (insn[0] & 0x0f) {
|
|
case 0x02: /* llhrl */
|
|
case 0x04: /* lghrl */
|
|
case 0x05: /* lhrl */
|
|
case 0x06: /* llghrl */
|
|
case 0x07: /* sthrl */
|
|
case 0x08: /* lgrl */
|
|
case 0x0b: /* stgrl */
|
|
case 0x0c: /* lgfrl */
|
|
case 0x0d: /* lrl */
|
|
case 0x0e: /* llgfrl */
|
|
case 0x0f: /* strl */
|
|
return true;
|
|
}
|
|
break;
|
|
case 0xc6:
|
|
switch (insn[0] & 0x0f) {
|
|
case 0x02: /* pfdrl */
|
|
case 0x04: /* cghrl */
|
|
case 0x05: /* chrl */
|
|
case 0x06: /* clghrl */
|
|
case 0x07: /* clhrl */
|
|
case 0x08: /* cgrl */
|
|
case 0x0a: /* clgrl */
|
|
case 0x0c: /* cgfrl */
|
|
case 0x0d: /* crl */
|
|
case 0x0e: /* clgfrl */
|
|
case 0x0f: /* clrl */
|
|
return true;
|
|
}
|
|
break;
|
|
}
|
|
return false;
|
|
}
|