forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

[S390] mm: fix storage key handling

Browse source 
page_get_storage_key() and page_set_storage_key() expect a page address
and not its page frame number. This got inconsistent with 2d42552d
"[S390] merge page_test_dirty and page_clear_dirty".

Result is that we read/write storage keys from random pages and do not
have a working dirty bit tracking at all.
E.g. SetPageUpdate() doesn't clear the dirty bit of requested pages, which
for example ext4 doesn't like very much and panics after a while.

Unable to handle kernel paging request at virtual user address (null)
Oops: 0004 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 1 Not tainted 2.6.39-07551-g139f37f-dirty #152
Process flush-94:0 (pid: 1576, task: 000000003eb34538, ksp: 000000003c287b70)
Krnl PSW : 0704c00180000000 0000000000316b12 (jbd2_journal_file_inode+0x10e/0x138)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
Krnl GPRS: 0000000000000000 0000000000000000 0000000000000000 0700000000000000
           0000000000316a62 000000003eb34cd0 0000000000000025 000000003c287b88
           0000000000000001 000000003c287a70 000000003f1ec678 000000003f1ec000
           0000000000000000 000000003e66ec00 0000000000316a62 000000003c287988
Krnl Code: 0000000000316b04: f0a0000407f4       srp     4(11,%r0),2036,0
           0000000000316b0a: b9020022           ltgr    %r2,%r2
           0000000000316b0e: a7740015           brc     7,316b38
          >0000000000316b12: e3d0c0000024       stg     %r13,0(%r12)
           0000000000316b18: 4120c010           la      %r2,16(%r12)
           0000000000316b1c: 4130d060           la      %r3,96(%r13)
           0000000000316b20: e340d0600004       lg      %r4,96(%r13)
           0000000000316b26: c0e50002b567       brasl   %r14,36d5f4
Call Trace:
([<0000000000316a62>] jbd2_journal_file_inode+0x5e/0x138)
 [<00000000002da13c>] mpage_da_map_and_submit+0x2e8/0x42c
 [<00000000002daac2>] ext4_da_writepages+0x2da/0x504
 [<00000000002597e8>] writeback_single_inode+0xf8/0x268
 [<0000000000259f06>] writeback_sb_inodes+0xd2/0x18c
 [<000000000025a700>] writeback_inodes_wb+0x80/0x168
 [<000000000025aa92>] wb_writeback+0x2aa/0x324
 [<000000000025abde>] wb_do_writeback+0xd2/0x274
 [<000000000025ae3a>] bdi_writeback_thread+0xba/0x1c4
 [<00000000001737be>] kthread+0xa6/0xb0
 [<000000000056c1da>] kernel_thread_starter+0x6/0xc
 [<000000000056c1d4>] kernel_thread_starter+0x0/0xc
INFO: lockdep is turned off.
Last Breaking-Event-Address:
 [<0000000000316a8a>] jbd2_journal_file_inode+0x86/0x138

Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
This commit is contained in:
Heiko Carstens 2011-05-29 12:40:50 +02:00
commit a43a9d93d4
2 changed files with 9 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

16
arch/s390/include/asm/pgtable.h
View file

@ -577,16 +577,16 @@ static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste) static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste)
{ {
#ifdef CONFIG_PGSTE #ifdef CONFIG_PGSTE
unsigned long pfn, bits; unsigned long address, bits;
unsigned char skey; unsigned char skey;
pfn = pte_val(*ptep) >> PAGE_SHIFT; address = pte_val(*ptep) & PAGE_MASK;
skey = page_get_storage_key(pfn); skey = page_get_storage_key(address);
bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
/* Clear page changed & referenced bit in the storage key */ /* Clear page changed & referenced bit in the storage key */
if (bits) { if (bits) {
skey ^= bits; skey ^= bits;
page_set_storage_key(pfn, skey, 1); page_set_storage_key(address, skey, 1);
} }
/* Transfer page changed & referenced bit to guest bits in pgste */ /* Transfer page changed & referenced bit to guest bits in pgste */
pgste_val(pgste) |= bits << 48; /* RCP_GR_BIT & RCP_GC_BIT */ pgste_val(pgste) |= bits << 48; /* RCP_GR_BIT & RCP_GC_BIT */
@ -628,16 +628,16 @@ static inline pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste)
static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste) static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste)
{ {
#ifdef CONFIG_PGSTE #ifdef CONFIG_PGSTE
unsigned long pfn; unsigned long address;
unsigned long okey, nkey; unsigned long okey, nkey;
pfn = pte_val(*ptep) >> PAGE_SHIFT; address = pte_val(*ptep) & PAGE_MASK;
okey = nkey = page_get_storage_key(pfn); okey = nkey = page_get_storage_key(address);
nkey &= ~(_PAGE_ACC_BITS | _PAGE_FP_BIT); nkey &= ~(_PAGE_ACC_BITS | _PAGE_FP_BIT);
/* Set page access key and fetch protection bit from pgste */ /* Set page access key and fetch protection bit from pgste */
nkey |= (pgste_val(pgste) & (RCP_ACC_BITS | RCP_FP_BIT)) >> 56; nkey |= (pgste_val(pgste) & (RCP_ACC_BITS | RCP_FP_BIT)) >> 56;
if (okey != nkey) if (okey != nkey)
page_set_storage_key(pfn, nkey, 1); page_set_storage_key(address, nkey, 1);
#endif #endif
} }

2
include/linux/page-flags.h
View file

@ -308,7 +308,7 @@ static inline void SetPageUptodate(struct page *page)
{ {
#ifdef CONFIG_S390 #ifdef CONFIG_S390
if (!test_and_set_bit(PG_uptodate, &page->flags)) if (!test_and_set_bit(PG_uptodate, &page->flags))
page_set_storage_key(page_to_pfn(page), PAGE_DEFAULT_KEY, 0); page_set_storage_key(page_to_phys(page), PAGE_DEFAULT_KEY, 0);
#else #else
/* /*
* Memory barrier must be issued before setting the PG_uptodate bit, * Memory barrier must be issued before setting the PG_uptodate bit,