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From: jcm@redhat.com (Jon Masters)
To: linux-arm-kernel@lists.infradead.org
Subject: [Linaro-acpi] Touching the initrd before paging_init
Date: Tue, 15 Dec 2015 10:29:54 -0500	[thread overview]
Message-ID: <567031F2.8060102@redhat.com> (raw)
In-Reply-To: <yw1xd1u8gcnk.fsf@unicorn.mansr.com>

On 12/15/2015 06:43 AM, M?ns Rullg?rd wrote:
> Jon Masters <jcm@redhat.com> writes:

>> But the reading of that cpio content into the new table locations is
>> done using the kernel memcpy routine to early_ioremap'd memory (Device
>> memory), which is architecturally sensitive to missaligned accesses.
> 
> As others have pointed out, your error is twofold: first using
> early_ioremap() when early_memremap() would do, then using regular
> memcpy() and not memcpy_fromio() on that.  Seems like your precious ACPI
> code is to blame here.

So I get that this could be changed. But I still want to understand
whether memcpy is behaving correctly. Will it guaranteed /never/ occur
that a copy will involve Device memory? All other such occurrences in
the kernel will be caught and fixed so this will never be an issue?

Jon.

  reply	other threads:[~2015-12-15 15:29 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-13  8:47 Touching the initrd before paging_init Jon Masters
2015-12-07  6:05 ` Mark Rutland
2015-12-13 16:54   ` [Linaro-acpi] " G Gregory
2015-12-13 16:59 ` Leif Lindholm
2015-12-13 21:36   ` Jon Masters
2015-12-13 22:02     ` Jon Masters
2015-12-13 22:15       ` G Gregory
2015-12-13 22:19         ` Jon Masters
2015-12-15 11:19           ` G Gregory
2015-12-15 15:36             ` Jon Masters
2015-12-15 16:13               ` G Gregory
2015-12-15 16:28                 ` G Gregory
2015-12-15 16:31                   ` Jon Masters
2015-12-15 17:08                     ` G Gregory
2015-12-15 19:22                       ` G Gregory
2015-12-13 22:15       ` Jon Masters
2015-12-15  4:51         ` Jon Masters
2015-12-15 10:14           ` Leif Lindholm
2015-12-15 10:22           ` Mark Rutland
2015-12-15 11:43           ` Måns Rullgård
2015-12-15 15:29             ` Jon Masters [this message]
2015-12-15 15:42               ` Mark Rutland
2015-12-15 16:31               ` Måns Rullgård

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