kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

powerpc fixes for 4.14 #5

Browse source 
A fix for a bad bug (written by me) in our livepatch handler. Removal of an
 over-zealous lockdep_assert_cpus_held() in our topology code. A fix to the
 recently added emulation of cntlz[wd]. And three small fixes to the recently
 added IMC PMU driver.
 
 Thanks to:
   Anju T Sudhakar, Balbir Singh, Kamalesh Babulal, Naveen N. Rao, Sandipan Das,
   Santosh Sivaraj, Thiago Jung Bauermann.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJZ4JXVAAoJEFHr6jzI4aWAi9MQAMBJLPG62uDmuhRY6v1MLp44
 8iVvNqTSGXuzz2c293Zo3Y8LHQ28S7f5wdwZs75fZ6GVup033pkuhL8XipFTB87m
 RzotMwJ1V1H0J7RRsDZ+QcyybwfE4GdqRHLjSU5VIUwJu7cQSIjjNWdkPUqswzXI
 g3BbNoxEOlEx31NbyNB+as7AnSvS0lLMvwB7TEy9rf3mmadN3UiAl3OJ93M/7Nm2
 qCWjCib/gUQ5U4N5STKWl62yGyvJ330OHoWdsTlHzHgYsEatQFHN8mjnW+UPN3rR
 Mz+xCIkt6PnYMdiJNXND42iwdx/7C7BR9JhQ5t6150Swfnbe+CT5nBxk2+IDKpQu
 V1rSX4S18TLQ+YCQm0wKuaQs/0EZ4kiHqUDZYVP/YQLSSYM5Ftf4W94Dwu+AZdtr
 wWX3szZxqvCZjvdT8HWQQW8vAIqpdxOkr019fjoUzcDoUIYKs3cLDJVx6CAY6n3t
 GGN3oGhffKbg1NyldDrZRDBJ+ie7gGincxlcMe1YrXDsXNum6edAhu01cUz7o9vO
 b9/fIPjWAWotS7kqWXgGfZL6vlRx3cdSh58vKaThmNAbZLaIAnPTYUynXqXZ++Nn
 bBDQUE9zwJ42ZgzYDr3bT6+9pwqPQ3w8zmOjZGB/J1ygS8k9/0gYVe1FO2N8vElM
 w5VBKl69v2RwItwHuSRJ
 =wWnt
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "A fix for a bad bug (written by me) in our livepatch handler. Removal
  of an over-zealous lockdep_assert_cpus_held() in our topology code. A
  fix to the recently added emulation of cntlz[wd]. And three small
  fixes to the recently added IMC PMU driver.

  Thanks to: Anju T Sudhakar, Balbir Singh, Kamalesh Babulal, Naveen N.
  Rao, Sandipan Das, Santosh Sivaraj, Thiago Jung Bauermann"

* tag 'powerpc-4.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/perf: Fix IMC initialization crash
  powerpc/perf: Add ___GFP_NOWARN flag to alloc_pages_node()
  powerpc/perf: Fix for core/nest imc call trace on cpuhotplug
  powerpc: Don't call lockdep_assert_cpus_held() from arch_update_cpu_topology()
  powerpc/lib/sstep: Fix count leading zeros instructions
  powerpc/livepatch: Fix livepatch stack access
This commit is contained in:
Linus Torvalds 2017-10-13 11:39:28 -07:00
commit e18e884445
4 changed files with 53 additions and 38 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

45
arch/powerpc/kernel/trace/ftrace_64_mprofile.S
View file

@ -181,34 +181,25 @@ _GLOBAL(ftrace_stub)
* - we have no stack frame and can not allocate one
* - LR points back to the original caller (in A)
* - CTR holds the new NIP in C
* - r0 & r12 are free
*
* r0 can't be used as the base register for a DS-form load or store, so
* we temporarily shuffle r1 (stack pointer) into r0 and then put it back.
* - r0, r11 & r12 are free
*/
livepatch_handler:
CURRENT_THREAD_INFO(r12, r1)
/* Save stack pointer into r0 */
mr r0, r1
/* Allocate 3 x 8 bytes */
ld r1, TI_livepatch_sp(r12)
addi r1, r1, 24
std r1, TI_livepatch_sp(r12)
ld r11, TI_livepatch_sp(r12)
addi r11, r11, 24
std r11, TI_livepatch_sp(r12)
/* Save toc & real LR on livepatch stack */
std r2, -24(r1)
std r2, -24(r11)
mflr r12
std r12, -16(r1)
std r12, -16(r11)
/* Store stack end marker */
lis r12, STACK_END_MAGIC@h
ori r12, r12, STACK_END_MAGIC@l
std r12, -8(r1)
/* Restore real stack pointer */
mr r1, r0
std r12, -8(r11)
/* Put ctr in r12 for global entry and branch there */
mfctr r12
@ -216,36 +207,30 @@ livepatch_handler:
/*
* Now we are returning from the patched function to the original
* caller A. We are free to use r0 and r12, and we can use r2 until we
* caller A. We are free to use r11, r12 and we can use r2 until we
* restore it.
*/
CURRENT_THREAD_INFO(r12, r1)
/* Save stack pointer into r0 */
mr r0, r1
ld r1, TI_livepatch_sp(r12)
ld r11, TI_livepatch_sp(r12)
/* Check stack marker hasn't been trashed */
lis r2, STACK_END_MAGIC@h
ori r2, r2, STACK_END_MAGIC@l
ld r12, -8(r1)
ld r12, -8(r11)
1: tdne r12, r2
EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0
/* Restore LR & toc from livepatch stack */
ld r12, -16(r1)
ld r12, -16(r11)
mtlr r12
ld r2, -24(r1)
ld r2, -24(r11)
/* Pop livepatch stack frame */
CURRENT_THREAD_INFO(r12, r0)
subi r1, r1, 24
std r1, TI_livepatch_sp(r12)
/* Restore real stack pointer */
mr r1, r0
CURRENT_THREAD_INFO(r12, r1)
subi r11, r11, 24
std r11, TI_livepatch_sp(r12)
/* Return to original caller of live patched function */
blr

6
arch/powerpc/lib/sstep.c
View file

@ -1684,11 +1684,13 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
* Logical instructions
*/
case 26: /* cntlzw */
op->val = __builtin_clz((unsigned int) regs->gpr[rd]);
val = (unsigned int) regs->gpr[rd];
op->val = ( val ? __builtin_clz(val) : 32 );
goto logical_done;
#ifdef __powerpc64__
case 58: /* cntlzd */
op->val = __builtin_clzl(regs->gpr[rd]);
val = regs->gpr[rd];
op->val = ( val ? __builtin_clzl(val) : 64 );
goto logical_done;
#endif
case 28: /* and */

1
arch/powerpc/mm/numa.c
View file

@ -1438,7 +1438,6 @@ out:
int arch_update_cpu_topology(void)
{
lockdep_assert_cpus_held();
return numa_update_cpu_topology(true);
}

39
arch/powerpc/perf/imc-pmu.c
View file

@ -399,6 +399,20 @@ static void nest_imc_counters_release(struct perf_event *event)
/* Take the mutex lock for this node and then decrement the reference count */
mutex_lock(&ref->lock);
if (ref->refc == 0) {
/*
* The scenario where this is true is, when perf session is
* started, followed by offlining of all cpus in a given node.
*
* In the cpuhotplug offline path, ppc_nest_imc_cpu_offline()
* function set the ref->count to zero, if the cpu which is
* about to offline is the last cpu in a given node and make
* an OPAL call to disable the engine in that node.
*
*/
mutex_unlock(&ref->lock);
return;
}
ref->refc--;
if (ref->refc == 0) {
rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST,
@ -523,8 +537,8 @@ static int core_imc_mem_init(int cpu, int size)
/* We need only vbase for core counters */
mem_info->vbase = page_address(alloc_pages_node(phys_id,
GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE,
get_order(size)));
GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
__GFP_NOWARN, get_order(size)));
if (!mem_info->vbase)
return -ENOMEM;
@ -646,6 +660,20 @@ static void core_imc_counters_release(struct perf_event *event)
return;
mutex_lock(&ref->lock);
if (ref->refc == 0) {
/*
* The scenario where this is true is, when perf session is
* started, followed by offlining of all cpus in a given core.
*
* In the cpuhotplug offline path, ppc_core_imc_cpu_offline()
* function set the ref->count to zero, if the cpu which is
* about to offline is the last cpu in a given core and make
* an OPAL call to disable the engine in that core.
*
*/
mutex_unlock(&ref->lock);
return;
}
ref->refc--;
if (ref->refc == 0) {
rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE,
@ -763,8 +791,8 @@ static int thread_imc_mem_alloc(int cpu_id, int size)
* free the memory in cpu offline path.
*/
local_mem = page_address(alloc_pages_node(phys_id,
GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE,
get_order(size)));
GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
__GFP_NOWARN, get_order(size)));
if (!local_mem)
return -ENOMEM;
@ -1148,7 +1176,8 @@ static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
}
/* Only free the attr_groups which are dynamically allocated */
kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs);
if (pmu_ptr->attr_groups[IMC_EVENT_ATTR])
kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs);
kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]);
kfree(pmu_ptr);
return;