lkml.org 
[lkml]   [2019]   [Aug]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v11 2/7] powerpc/mce: Fix MCE handling for huge pages
Date
From: Balbir Singh <bsingharora@gmail.com>

The current code would fail on huge pages addresses, since the shift would
be incorrect. Use the correct page shift value returned by
__find_linux_pte() to get the correct physical address. The code is more
generic and can handle both regular and compound pages.

Fixes: ba41e1e1ccb9 ("powerpc/mce: Hookup derror (load/store) UE errors")
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[arbab@linux.ibm.com: Fixup pseries_do_memory_failure()]
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Tested-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Cc: stable@vger.kernel.org # v4.15+
---
arch/powerpc/kernel/mce_power.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c
index a814d2dfb5b0..714a98e0927f 100644
--- a/arch/powerpc/kernel/mce_power.c
+++ b/arch/powerpc/kernel/mce_power.c
@@ -26,6 +26,7 @@
unsigned long addr_to_pfn(struct pt_regs *regs, unsigned long addr)
{
pte_t *ptep;
+ unsigned int shift;
unsigned long flags;
struct mm_struct *mm;

@@ -35,13 +36,18 @@ unsigned long addr_to_pfn(struct pt_regs *regs, unsigned long addr)
mm = &init_mm;

local_irq_save(flags);
- if (mm == current->mm)
- ptep = find_current_mm_pte(mm->pgd, addr, NULL, NULL);
- else
- ptep = find_init_mm_pte(addr, NULL);
+ ptep = __find_linux_pte(mm->pgd, addr, NULL, &shift);
local_irq_restore(flags);
+
if (!ptep || pte_special(*ptep))
return ULONG_MAX;
+
+ if (shift > PAGE_SHIFT) {
+ unsigned long rpnmask = (1ul << shift) - PAGE_SIZE;
+
+ return pte_pfn(__pte(pte_val(*ptep) | (addr & rpnmask)));
+ }
+
return pte_pfn(*ptep);
}

@@ -344,7 +350,7 @@ static const struct mce_derror_table mce_p9_derror_table[] = {
MCE_INITIATOR_CPU, MCE_SEV_SEVERE, true },
{ 0, false, 0, 0, 0, 0, 0 } };

-static int mce_find_instr_ea_and_pfn(struct pt_regs *regs, uint64_t *addr,
+static int mce_find_instr_ea_and_phys(struct pt_regs *regs, uint64_t *addr,
uint64_t *phys_addr)
{
/*
@@ -541,7 +547,8 @@ static int mce_handle_derror(struct pt_regs *regs,
* kernel/exception-64s.h
*/
if (get_paca()->in_mce < MAX_MCE_DEPTH)
- mce_find_instr_ea_and_pfn(regs, addr, phys_addr);
+ mce_find_instr_ea_and_phys(regs, addr,
+ phys_addr);
}
found = 1;
}
--
2.21.0
\
 
 \ /
  Last update: 2019-08-20 10:17    [W:0.069 / U:2.376 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site