Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1620341
| Path | csiph.com!news.mixmin.net!news.unit0.net!news.panservice.it!bofh.it!news.nic.it!robomod |
|---|---|
| From | Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Newsgroups | linux.kernel |
| Subject | [PATCH 4.10 046/110] powerpc/crypto/crc32c-vpmsum: Fix missing preempt_disable() |
| Date | Mon, 10 Apr 2017 19:00:04 +0200 |
| Message-ID | <tuKPy-3hW-65@gated-at.bofh.it> (permalink) |
| References | <tuKPv-3hW-3@gated-at.bofh.it> |
| X-Original-To | linux-kernel@vger.kernel.org |
| X-Mailer | git-send-email 2.12.2 |
| User-Agent | quilt/0.65 |
| MIME-Version | 1.0 |
| Content-Type | text/plain; charset=UTF-8 |
| Sender | robomod@news.nic.it |
| List-ID | <linux-kernel.vger.kernel.org> |
| X-Mailing-List | linux-kernel@vger.kernel.org |
| Approved | robomod@news.nic.it |
| Lines | 72 |
| Organization | linux.* mail to news gateway |
| X-Original-Cc | Greg Kroah-Hartman <gregkh@linuxfoundation.org>, stable@vger.kernel.org, Michael Ellerman <mpe@ellerman.id.au> |
| X-Original-Date | Mon, 10 Apr 2017 18:42:37 +0200 |
| X-Original-Message-ID | <20170410164203.785490478@linuxfoundation.org> |
| X-Original-References | <20170410164201.247583164@linuxfoundation.org> |
| X-Original-Sender | linux-kernel-owner@vger.kernel.org |
| Xref | csiph.com linux.kernel:1620341 |
Show key headers only | View raw
4.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Michael Ellerman <mpe@ellerman.id.au>
commit 4749228f022893faf54a3dbc70796f78b7d4f342 upstream.
In crc32c_vpmsum() we call enable_kernel_altivec() without first
disabling preemption, which is not allowed:
WARNING: CPU: 9 PID: 2949 at ../arch/powerpc/kernel/process.c:277 enable_kernel_altivec+0x100/0x120
Modules linked in: dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio libcrc32c vmx_crypto ...
CPU: 9 PID: 2949 Comm: docker Not tainted 4.11.0-rc5-compiler_gcc-6.3.1-00033-g308ac7563944 #381
...
NIP [c00000000001e320] enable_kernel_altivec+0x100/0x120
LR [d000000003df0910] crc32c_vpmsum+0x108/0x150 [crc32c_vpmsum]
Call Trace:
0xc138fd09 (unreliable)
crc32c_vpmsum+0x108/0x150 [crc32c_vpmsum]
crc32c_vpmsum_update+0x3c/0x60 [crc32c_vpmsum]
crypto_shash_update+0x88/0x1c0
crc32c+0x64/0x90 [libcrc32c]
dm_bm_checksum+0x48/0x80 [dm_persistent_data]
sb_check+0x84/0x120 [dm_thin_pool]
dm_bm_validate_buffer.isra.0+0xc0/0x1b0 [dm_persistent_data]
dm_bm_read_lock+0x80/0xf0 [dm_persistent_data]
__create_persistent_data_objects+0x16c/0x810 [dm_thin_pool]
dm_pool_metadata_open+0xb0/0x1a0 [dm_thin_pool]
pool_ctr+0x4cc/0xb60 [dm_thin_pool]
dm_table_add_target+0x16c/0x3c0
table_load+0x184/0x400
ctl_ioctl+0x2f0/0x560
dm_ctl_ioctl+0x38/0x50
do_vfs_ioctl+0xd8/0x920
SyS_ioctl+0x68/0xc0
system_call+0x38/0xfc
It used to be sufficient just to call pagefault_disable(), because that
also disabled preemption. But the two were decoupled in commit 8222dbe21e79
("sched/preempt, mm/fault: Decouple preemption from the page fault
logic") in mid 2015.
So add the missing preempt_disable/enable(). We should also call
disable_kernel_fp(), although it does nothing by default, there is a
debug switch to make it active and all enables should be paired with
disables.
Fixes: 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/powerpc/crypto/crc32c-vpmsum_glue.c | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/powerpc/crypto/crc32c-vpmsum_glue.c
+++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
@@ -33,10 +33,13 @@ static u32 crc32c_vpmsum(u32 crc, unsign
}
if (len & ~VMX_ALIGN_MASK) {
+ preempt_disable();
pagefault_disable();
enable_kernel_altivec();
crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK);
+ disable_kernel_altivec();
pagefault_enable();
+ preempt_enable();
}
tail = len & VMX_ALIGN_MASK;
Back to linux.kernel | Previous | Next | Find similar | Unroll thread
[PATCH 4.10 046/110] powerpc/crypto/crc32c-vpmsum: Fix missing preempt_disable() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-10 19:00 +0200
csiph-web