OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

powerpc fixes for 4.17 #7 

Just one fix, to make sure the PCR (Processor Compatibility Register) is reset
 on boot. Otherwise if we're running in compat mode in a guest (eg. pretending a
 Power9 is a Power8) and the host kernel oopses and kdumps then the kdump
 kernel's userspace will be running in Power8 mode, and will SIGILL if it uses
 Power9-only instructions.
 
 Thanks to:
   Michael Neuling.
 -----BEGIN PGP SIGNATURE-----
 
 iQIwBAABCAAaBQJbB/PjExxtcGVAZWxsZXJtYW4uaWQuYXUACgkQUevqPMjhpYCK
 rhAAh2zSxZfpvDkjvWwqD26yDiDRcVV+rU2CtDiFQk+tAWVFhFqEMJvPWaUU4Ub9
 EQStTS4gLiYsY282M+TyFGoUX76aAlMJenaCak8YQmYA4DQ8Sv2LB/jTJBhvbVnC
 5ig9aNhSef5aDS7i5r5XzITf+SQ+1U2wddMxzy5Oklku+ypFX3cj9MtNvcD+fJIK
 D35vvv5kI2a3wZsE/R7TB91MmfLgWY/4fb4da+dXMVTm+E1gHgOOU7JcnmzEJ/fH
 Ds3d8JiIvsFXPCSwCruLiTXtmzQjZUYK3p81ffD7f3qCLBb54PbNBvsFgMYq4h8k
 JGNeTqo+gGq3rqqbsftSudHVfG9jleKiJk7Xng3m5iqADHioroq0WTxulZczFd7t
 DIl3NcmPnl7kFG/OjO39EDg50+Y/o0+uurjiy3EB9xTtivnOQ0Os+7tvmeqnzL8y
 RpXVtZ0Uvf1aBrfXaobz/uNGy4Zy0ZamzdyxfLup7gqtPdAnDVnRak2Cn5bKuqK0
 Xsi7/liq6Y7mwtys+iFuCMthh4/wza43VyH+ZYleEXOe6c0hfnuAvQdGcRSDtLMh
 arSXYKbJCzwaQXKiTL5VRf/ta51MVi22ghV9/72Cf0wYUMJe0SNDYkhn34C8KlxB
 Z5xYHljqRZE/uD8lYeeSdZKMvNEcinEJSpaC645uJVcvkKA=
 =lmT9
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fix from Michael Ellerman:
 "Just one fix, to make sure the PCR (Processor Compatibility Register)
  is reset on boot.

  Otherwise if we're running in compat mode in a guest (eg. pretending a
  Power9 is a Power8) and the host kernel oopses and kdumps then the
  kdump kernel's userspace will be running in Power8 mode, and will
  SIGILL if it uses Power9-only instructions.

  Thanks to Michael Neuling"

* tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Clear PCR on boot
This commit is contained in:
Linus Torvalds 2018-05-25 09:32:00 -07:00
parent f287fe35de faf37c44a1
commit b133ef6ea4
2 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/powerpc/kernel/cpu_setup_power.S
View File

@ -28,6 +28,7 @@ _GLOBAL(__setup_cpu_power7)
beqlr
li r0,0
mtspr SPRN_LPID,r0
mtspr SPRN_PCR,r0
mfspr r3,SPRN_LPCR
li r4,(LPCR_LPES1 >> LPCR_LPES_SH)
bl __init_LPCR_ISA206
@ -41,6 +42,7 @@ _GLOBAL(__restore_cpu_power7)
beqlr
li r0,0
mtspr SPRN_LPID,r0
mtspr SPRN_PCR,r0
mfspr r3,SPRN_LPCR
li r4,(LPCR_LPES1 >> LPCR_LPES_SH)
bl __init_LPCR_ISA206
@ -57,6 +59,7 @@ _GLOBAL(__setup_cpu_power8)
beqlr
li r0,0
mtspr SPRN_LPID,r0
mtspr SPRN_PCR,r0
mfspr r3,SPRN_LPCR
ori r3, r3, LPCR_PECEDH
li r4,0 /* LPES = 0 */
@ -78,6 +81,7 @@ _GLOBAL(__restore_cpu_power8)
beqlr
li r0,0
mtspr SPRN_LPID,r0
mtspr SPRN_PCR,r0
mfspr r3,SPRN_LPCR
ori r3, r3, LPCR_PECEDH
li r4,0 /* LPES = 0 */
@ -99,6 +103,7 @@ _GLOBAL(__setup_cpu_power9)
mtspr SPRN_PSSCR,r0
mtspr SPRN_LPID,r0
mtspr SPRN_PID,r0
mtspr SPRN_PCR,r0
mfspr r3,SPRN_LPCR
LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC)
or r3, r3, r4
@ -123,6 +128,7 @@ _GLOBAL(__restore_cpu_power9)
mtspr SPRN_PSSCR,r0
mtspr SPRN_LPID,r0
mtspr SPRN_PID,r0
mtspr SPRN_PCR,r0
mfspr r3,SPRN_LPCR
LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC)
or r3, r3, r4

1
arch/powerpc/kernel/dt_cpu_ftrs.c
View File

@ -101,6 +101,7 @@ static void __restore_cpu_cpufeatures(void)
if (hv_mode) {
mtspr(SPRN_LPID, 0);
mtspr(SPRN_HFSCR, system_registers.hfscr);
mtspr(SPRN_PCR, 0);
}
mtspr(SPRN_FSCR, system_registers.fscr);