projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| bd7abca0 GKH |
1 | From c8adfeccee01ce3de6a7d14fcd4e3be02e27f03c Mon Sep 17 00:00:00 2001 |
| 2 | From: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> | |
| 3 | Date: Mon, 1 Oct 2012 14:59:13 +0000 | |
| 4 | Subject: powerpc: Fix VMX fix for memcpy case | |
| 5 | ||
| 6 | From: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> | |
| 7 | ||
| 8 | commit c8adfeccee01ce3de6a7d14fcd4e3be02e27f03c upstream. | |
| 9 | ||
| 10 | In 2fae7cdb60240e2e2d9b378afbf6d9fcce8a3890 ("powerpc: Fix VMX in | |
| 11 | interrupt check in POWER7 copy loops"), Anton inadvertently | |
| 12 | introduced a regression for memcpy on POWER7 machines. copyuser and | |
| 13 | memcpy diverge slightly in their use of cr1 (copyuser doesn't use it, | |
| 14 | but memcpy does) and you end up clobbering that register with your fix. | |
| 15 | That results in (taken from an FC18 kernel): | |
| 16 | ||
| 17 | [ 18.824604] Unrecoverable VMX/Altivec Unavailable Exception f20 at c000000000052f40 | |
| 18 | [ 18.824618] Oops: Unrecoverable VMX/Altivec Unavailable Exception, sig: 6 [#1] | |
| 19 | [ 18.824623] SMP NR_CPUS=1024 NUMA pSeries | |
| 20 | [ 18.824633] Modules linked in: tg3(+) be2net(+) cxgb4(+) ipr(+) sunrpc xts lrw gf128mul dm_crypt dm_round_robin dm_multipath linear raid10 raid456 async_raid6_recov async_memcpy async_pq raid6_pq async_xor xor async_tx raid1 raid0 scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc scsi_dh_alua squashfs cramfs | |
| 21 | [ 18.824705] NIP: c000000000052f40 LR: c00000000020b874 CTR: 0000000000000512 | |
| 22 | [ 18.824709] REGS: c000001f1fef7790 TRAP: 0f20 Not tainted (3.6.0-0.rc6.git0.2.fc18.ppc64) | |
| 23 | [ 18.824713] MSR: 8000000000009032 <SF,EE,ME,IR,DR,RI> CR: 4802802e XER: 20000010 | |
| 24 | [ 18.824726] SOFTE: 0 | |
| 25 | [ 18.824728] CFAR: 0000000000000f20 | |
| 26 | [ 18.824731] TASK = c000000fa7128400[0] 'swapper/24' THREAD: c000000fa7480000 CPU: 24 | |
| 27 | GPR00: 00000000ffffffc0 c000001f1fef7a10 c00000000164edc0 c000000f9b9a8120 | |
| 28 | GPR04: c000000f9b9a8124 0000000000001438 0000000000000060 03ffffff064657ee | |
| 29 | GPR08: 0000000080000000 0000000000000010 0000000000000020 0000000000000030 | |
| 30 | GPR12: 0000000028028022 c00000000ff25400 0000000000000001 0000000000000000 | |
| 31 | GPR16: 0000000000000000 7fffffffffffffff c0000000016b2180 c00000000156a500 | |
| 32 | GPR20: c000000f968c7a90 c0000000131c31d8 c000001f1fef4000 c000000001561d00 | |
| 33 | GPR24: 000000000000000a 0000000000000000 0000000000000001 0000000000000012 | |
| 34 | GPR28: c000000fa5c04f80 00000000000008bc c0000000015c0a28 000000000000022e | |
| 35 | [ 18.824792] NIP [c000000000052f40] .memcpy_power7+0x5a0/0x7c4 | |
| 36 | [ 18.824797] LR [c00000000020b874] .pcpu_free_area+0x174/0x2d0 | |
| 37 | [ 18.824800] Call Trace: | |
| 38 | [ 18.824803] [c000001f1fef7a10] [c000000000052c14] .memcpy_power7+0x274/0x7c4 (unreliable) | |
| 39 | [ 18.824809] [c000001f1fef7b10] [c00000000020b874] .pcpu_free_area+0x174/0x2d0 | |
| 40 | [ 18.824813] [c000001f1fef7bb0] [c00000000020ba88] .free_percpu+0xb8/0x1b0 | |
| 41 | [ 18.824819] [c000001f1fef7c50] [c00000000043d144] .throtl_pd_exit+0x94/0xd0 | |
| 42 | [ 18.824824] [c000001f1fef7cf0] [c00000000043acf8] .blkg_free+0x88/0xe0 | |
| 43 | [ 18.824829] [c000001f1fef7d90] [c00000000018c048] .rcu_process_callbacks+0x2e8/0x8a0 | |
| 44 | [ 18.824835] [c000001f1fef7e90] [c0000000000a8ce8] .__do_softirq+0x158/0x4d0 | |
| 45 | [ 18.824840] [c000001f1fef7f90] [c000000000025ecc] .call_do_softirq+0x14/0x24 | |
| 46 | [ 18.824845] [c000000fa7483650] [c000000000010e80] .do_softirq+0x160/0x1a0 | |
| 47 | [ 18.824850] [c000000fa74836f0] [c0000000000a94a4] .irq_exit+0xf4/0x120 | |
| 48 | [ 18.824854] [c000000fa7483780] [c000000000020c44] .timer_interrupt+0x154/0x4d0 | |
| 49 | [ 18.824859] [c000000fa7483830] [c000000000003be0] decrementer_common+0x160/0x180 | |
| 50 | [ 18.824866] --- Exception: 901 at .plpar_hcall_norets+0x84/0xd4 | |
| 51 | [ 18.824866] LR = .check_and_cede_processor+0x48/0x80 | |
| 52 | [ 18.824871] [c000000fa7483b20] [c00000000007f018] .check_and_cede_processor+0x18/0x80 (unreliable) | |
| 53 | [ 18.824877] [c000000fa7483b90] [c00000000007f104] .dedicated_cede_loop+0x84/0x150 | |
| 54 | [ 18.824883] [c000000fa7483c50] [c0000000006bc030] .cpuidle_enter+0x30/0x50 | |
| 55 | [ 18.824887] [c000000fa7483cc0] [c0000000006bc9f4] .cpuidle_idle_call+0x104/0x720 | |
| 56 | [ 18.824892] [c000000fa7483d80] [c000000000070af8] .pSeries_idle+0x18/0x40 | |
| 57 | [ 18.824897] [c000000fa7483df0] [c000000000019084] .cpu_idle+0x1a4/0x380 | |
| 58 | [ 18.824902] [c000000fa7483ec0] [c0000000008a4c18] .start_secondary+0x520/0x528 | |
| 59 | [ 18.824907] [c000000fa7483f90] [c0000000000093f0] .start_secondary_prolog+0x10/0x14 | |
| 60 | [ 18.824911] Instruction dump: | |
| 61 | [ 18.824914] 38840008 90030000 90e30004 38630008 7ca62850 7cc300d0 78c7e102 7cf01120 | |
| 62 | [ 18.824923] 78c60660 39200010 39400020 39600030 <7e00200c> 7c0020ce 38840010 409f001c | |
| 63 | [ 18.824935] ---[ end trace 0bb95124affaaa45 ]--- | |
| 64 | [ 18.825046] Unrecoverable VMX/Altivec Unavailable Exception f20 at c000000000052d08 | |
| 65 | ||
| 66 | I believe the right fix is to make memcpy match usercopy and not use | |
| 67 | cr1. | |
| 68 | ||
| 69 | Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> | |
| 70 | Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> | |
| 71 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 72 | ||
| 73 | --- | |
| 74 | arch/powerpc/lib/memcpy_power7.S | 4 ++-- | |
| 75 | 1 file changed, 2 insertions(+), 2 deletions(-) | |
| 76 | ||
| 77 | --- a/arch/powerpc/lib/memcpy_power7.S | |
| 78 | +++ b/arch/powerpc/lib/memcpy_power7.S | |
| 79 | @@ -239,8 +239,8 @@ _GLOBAL(memcpy_power7) | |
| 80 | ori r9,r9,1 /* stream=1 */ | |
| 81 | ||
| 82 | srdi r7,r5,7 /* length in cachelines, capped at 0x3FF */ | |
| 83 | - cmpldi cr1,r7,0x3FF | |
| 84 | - ble cr1,1f | |
| 85 | + cmpldi r7,0x3FF | |
| 86 | + ble 1f | |
| 87 | li r7,0x3FF | |
| 88 | 1: lis r0,0x0E00 /* depth=7 */ | |
| 89 | sldi r7,r7,7 |