Comment 20 for bug 521523

Quoting Paolo Bonzini (<email address hidden>):
> I'm seeing errors like this in /var/log/messages at the same time as
> corruptions:
>
> Feb 9 14:03:26 yakj kernel: [135241.310137] ecryptfs_read_and_validate_header_region: Error reading header region; rc = [-4]
> Feb 9 14:03:26 yakj kernel: [135241.310146] ecryptfs_decrypt_page: Error attempting to read lower page; rc = [-4]
> Feb 9 14:03:26 yakj kernel: [135241.310147] ecryptfs_readpage: Error decrypting page; rc = [-4]
>
> -4 is EINTR.

That sounds to me like the ecryptfs should retry. The reading of the lower
page just happened to get interrupted by a signal handler. Something like:

From bd6289242f82df4ef254b3e59d38dc39b9b2879d Mon Sep 17 00:00:00 2001
From: Serge E. Hallyn <email address hidden>
Date: Mon, 14 Feb 2011 14:48:22 +0000
Subject: [PATCH 1/1] ecryptfs: retry ecryptfs_read_and_validate_header_region on -EINTR

Signed-off-by: Serge E. Hallyn <email address hidden>
---
 fs/ecryptfs/crypto.c | 6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index bfd8b68..81d5fa7 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1211,8 +1211,10 @@ int ecryptfs_read_and_validate_header_region(char *data,

  if (crypt_stat->extent_size == 0)
   crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
- rc = ecryptfs_read_lower(data, 0, crypt_stat->extent_size,
- ecryptfs_inode);
+ do {
+ rc = ecryptfs_read_lower(data, 0, crypt_stat->extent_size,
+ ecryptfs_inode);
+ } while (rc == -EINTR);
  if (rc < 0) {
   printk(KERN_ERR "%s: Error reading header region; rc = [%d]\n",
          __func__, rc);
--
1.7.0.4

totally untested.

-serge