Re: [PATCH v2] prctl.2, proc.5: Document VMA naming

[Alejandro Colomar <alx.manpages@gmail.com>]

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On 1/11/23 00:02, Pasha Tatashin wrote:
> On Tue, Jan 10, 2023 at 5:56 PM Suren Baghdasaryan <surenb@google.com> wrote:
>>
>> On Tue, Jan 10, 2023 at 1:12 PM Alejandro Colomar
>> <alx.manpages@gmail.com> wrote:
>>>
>>> Hi Nick and Suren!
>>>
>>> On 1/10/23 22:02, Suren Baghdasaryan wrote:
>>>> On Sat, Jan 7, 2023 at 2:19 PM Nick Gregory <nick@nickgregory.me> wrote:
>>>>>
>>>>> Bring in man page changes from the patch set by Colin Cross
>>>>> <ccross@google.com> [0], and document the corresponding virtual names in
>>>>> procfs.
>>>>
>>>> Hi Nick,
>>>> The content LGTM (not an expert in formatting).
>>>
>>> The formatting is perfect, AFAICS. :)
>>>
>>>> You even captured the
>>>> recent addition of named shared anonymous mapping support (CC'ing
>>>> Pasha)! Thanks for doing this!
>>>
>>> Do you want me to wait for him to have a look, or should I just apply?
>>
>> I CC'ed Pasha as FYI. I don't think he will have any objections.
>> Thanks for checking!
>>
>>>
>>>>
>>>>>
>>>>> Signed-off-by: Nick Gregory <nick@nickgregory.me>
>>>>> Cc: Colin Cross <ccross@google.com>
>>>>> Cc: Suren Baghdasaryan <surenb@google.com>
>>>>> Cc: Kees Cook <keescook@chromium.org>
>>>>
>>>> Reviewed-by: Suren Baghdasaryan <surenb@google.com>
>>>
>>> Thanks for the patch and the review!
>>>
>>> Cheers,
>>>
>>> Alex
>>>
>>>>
>>>>>
>>>>> [0] https://lore.kernel.org/linux-mm/20211019215511.3771969-2-surenb@google.com/
>>>>> ---
>>>>>    man2/prctl.2 | 34 ++++++++++++++++++++++++++++++++++
>>>>>    man5/proc.5  | 14 ++++++++++++++
>>>>>    2 files changed, 48 insertions(+)
>>>>>
>>>>> diff --git a/man2/prctl.2 b/man2/prctl.2
>>>>> index 74f86ff49..2c8d52ade 100644
>>>>> --- a/man2/prctl.2
>>>>> +++ b/man2/prctl.2
>>>>> @@ -769,6 +769,40 @@ This feature is available only if the kernel is built with the
>>>>>    .B CONFIG_CHECKPOINT_RESTORE
>>>>>    option enabled.
>>>>>    .RE
>>>>> +.\" prctl PR_SET_VMA
>>>>> +.TP
>>>>> +.BR PR_SET_VMA " (since Linux 5.17)"
>>>>> +.\" Commit 9a10064f5625d5572c3626c1516e0bebc6c9fe9b
>>>>> +Sets an attribute specified in
>>>>> +.I arg2
>>>>> +for virtual memory areas starting from the address specified in
>>>>> +.I arg3
>>>>> +and spanning the size specified in
>>>>> +.IR arg4 .
>>>>> +.I arg5
>>>>> +specifies the value of the attribute to be set.
>>>>> +.IP
>>>>> +Note that assigning an attribute to a virtual memory area
>>>>> +might prevent it from being merged with adjacent virtual memory areas
>>>>> +due to the difference in that attribute's value.
>>>>> +.IP
>>>>> +Currently,
>>>>> +.I arg2
>>>>> +must be one of:
>>>>> +.RS
>>>>> +.TP
>>>>> +.B PR_SET_VMA_ANON_NAME
>>>>> +Set a name for anonymous virtual memory areas.
>>>>> +.I arg5
>>>>> +should be a pointer to a null-terminated string containing the name.
>>>>> +The name length including null byte cannot exceed 80 bytes.
>>>>> +If
>>>>> +.I arg5
>>>>> +is NULL, the name of the appropriate anonymous virtual memory areas
>>>>> +will be reset.
>>>>> +The name can contain only printable ascii characters (including space),
>>>>> +except \(aq[\(aq, \(aq]\(aq, \(aq\e\(aq, \(aq$\(aq, and \(aq\(ga\(aq.
>>>>> +.RE
>>>>>    .\" prctl PR_MPX_ENABLE_MANAGEMENT
>>>>>    .TP
>>>>>    .BR PR_MPX_ENABLE_MANAGEMENT ", " PR_MPX_DISABLE_MANAGEMENT " (since Linux 3.19, removed in Linux 5.4; only on x86)"
>>>>> diff --git a/man5/proc.5 b/man5/proc.5
>>>>> index 65a4c38e3..e0a64d486 100644
>>>>> --- a/man5/proc.5
>>>>> +++ b/man5/proc.5
>>>>> @@ -1372,6 +1372,20 @@ See
>>>>>    .TP
>>>>>    .I [heap]
>>>>>    The process's heap.
>>>>> +.TP
>>>>> +.IR [anon: name ] " (since Linux 5.17)"
>>>>> +.\" Commit 9a10064f5625d5572c3626c1516e0bebc6c9fe9b
>>>>> +A named private anonymous mapping.
>>>>> +Set with
>>>>> +.BR prctl (2)
>>>>> +.BR PR_SET_VMA_ANON_NAME .
>>>>> +.TP
>>>>> +.IR [anon_shmem: name ] " (since Linux 6.2)"
>>>>> +.\" Commit d09e8ca6cb93bb4b97517a18fbbf7eccb0e9ff43
>>>>> +A named shared anonymous mapping.
>>>>> +Set with
>>>>> +.BR prctl (2)
>>>>> +.BR PR_SET_VMA_ANON_NAME .
> 
> LGTM, thank you
> 
> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>

This tag is out just for a few seconds :P

Cheers,

Alex

> 
> Pasha

-- 
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