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From: Samuel Thibault <samuel.thibault@gnu.org>
To: Sergey Bugaev <bugaevc@gmail.com>
Cc: libc-alpha@sourceware.org, bug-hurd@gnu.org
Subject: Re: [RFC PATCH glibc 25/34] hurd: Improve reply port handling when exiting signal handlers
Date: Tue, 11 Apr 2023 22:15:28 +0200	[thread overview]
Message-ID: <20230411201528.pijuosntav2jcskh@begin> (raw)
In-Reply-To: <CAN9u=HcLem9NdM-koH6G+QQAtVLWWW2ke=TeH-=PwcZWHrGUNA@mail.gmail.com>

Sergey Bugaev, le mar. 11 avril 2023 10:44:17 +0300, a ecrit:
> On Tue, Apr 11, 2023 at 1:03 AM Samuel Thibault <samuel.thibault@gnu.org> wrote:
> > I tend to be very cautious with reply port reuse since it can confuse
> > servers a lot when e.g. interrupted, so it's generally safer not to try
> > to reuse them.
> 
> Huh? Confuse how?

On interruption, it's hard to know whether the server will actually send
a message on the reply port or not, in the end. So if you re-use a reply
port but unfortunately the server sent a reply on it in the end, you get
all reply messages shifted.

> But I don't see a reason to destroy the *current* reply port, the one
> used during signal handling, which we're longjumping out of.

Simplicity. I agree that it should work fine as of now. But then
somebody contributes something, doesn't notice that case, breaks it and
mayhem comes, but only rarely since signals don't happen often.

> On the other hand it doesn't hurt much either, and signal handling is
> a slow path anyway, so we may just play it safe.

Yes, please :)

Samuel

  reply	other threads:[~2023-04-11 20:15 UTC|newest]

Thread overview: 140+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-19 15:09 [RFC PATCH 00/34] The rest of the x86_64-gnu port Sergey Bugaev
2023-03-19 15:09 ` [RFC PATCH gnumach 01/34] Add i386_fsgs_base_state Sergey Bugaev
2023-04-02 22:43   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH gnumach 02/34] Remove bootstrap.defs Sergey Bugaev
2023-04-02 22:43   ` Samuel Thibault
2023-04-03  9:39     ` Sergey Bugaev
2023-03-19 15:09 ` [RFC PATCH gnumach 03/34] Make exception subcode a long Sergey Bugaev
2023-04-02 22:45   ` Samuel Thibault
2023-04-03  9:32     ` Sergey Bugaev
2023-04-06  2:11       ` Flávio Cruz
2023-04-10 23:52         ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 04/34] hurd: " Sergey Bugaev
2023-04-02 22:52   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 05/34] hurd: Remove __hurd_threadvar_stack_{offset,mask} Sergey Bugaev
2023-04-02 22:53   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 06/34] hurd: Swap around two function calls Sergey Bugaev
2023-04-02 22:54   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 07/34] hurd: Fix file name in #error Sergey Bugaev
2023-04-02 22:55   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 08/34] hurd: Disable O_TRUNC and FS_RETRY_MAGICAL in rtld Sergey Bugaev
2023-04-02 22:57   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 09/34] hurd: Fix _hurd_setup_sighandler () signature Sergey Bugaev
2023-04-02 22:58   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 10/34] stdio-common: Fix building when !IS_IN (libc) Sergey Bugaev
2023-04-02 23:01   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 11/34] mach, hurd: Drop __libc_lock_self0 Sergey Bugaev
2023-04-02 23:02   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 12/34] hurd: More 64-bit integer casting fixes Sergey Bugaev
2023-04-02 23:03   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 13/34] x86-64: Disable prefer_map_32bit_exec tunable on non-Linux Sergey Bugaev
2023-04-02 23:09   ` Samuel Thibault
2023-04-03 10:10     ` Sergey Bugaev
2023-04-03 19:02       ` H.J. Lu
2023-04-03 20:11         ` Sergey Bugaev
2023-03-19 15:09 ` [RFC PATCH glibc 14/34] hurd: Move rtld-strncpy-c.c out of mach/hurd/ Sergey Bugaev
2023-04-02 23:10   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 15/34] hurd: Use uintptr_t for register values in trampoline.c Sergey Bugaev
2023-04-02 23:13   ` Samuel Thibault
2023-03-19 15:09 ` [RFC PATCH glibc 16/34] hurd: Add sys/ucontext.h and sigcontext.h for x86_64 Sergey Bugaev
2023-04-10 18:39   ` Samuel Thibault
2023-04-10 19:07     ` Sergey Bugaev
2023-04-10 19:21       ` Samuel Thibault
2023-04-10 18:58   ` Samuel Thibault
2023-04-10 19:13     ` Sergey Bugaev
2023-04-10 19:21       ` Samuel Thibault
2023-04-10 21:50         ` Sergey Bugaev
2023-04-10 22:23           ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 17/34] hurd: Implement x86_64/intr-msg.h Sergey Bugaev
2023-04-10 18:41   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 18/34] hurd: Port trampoline.c to x86_64 Sergey Bugaev
2023-04-03 11:56   ` [PATCH v2 18.0/34] Alignment-respecting x86_64 trampoline.c Sergey Bugaev
2023-04-03 11:56     ` [PATCH v2 18.1/34] hurd: Do not declare local variables volatile Sergey Bugaev
2023-04-10 18:42       ` Samuel Thibault
2023-04-03 11:56     ` [PATCH v2 18.2/34] hurd: Port trampoline.c to x86_64 Sergey Bugaev
2023-04-10 19:04       ` Samuel Thibault
2023-04-10 21:33         ` Sergey Bugaev
2023-03-19 15:10 ` [RFC PATCH glibc 19/34] hurd: Move a couple of singal-related files to x86 Sergey Bugaev
2023-04-02 23:15   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 20/34] htl: Add tcb-offsets.sym for x86_64 Sergey Bugaev
2023-04-02 23:16   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 21/34] x86_64: Add rtld-stpncpy & rtld-strncpy Sergey Bugaev
2023-04-02 23:18   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 22/34] htl: Implement thread_set_pcsptp for x86_64 Sergey Bugaev
2023-04-02 23:19   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 23/34] elf: Stop including tls.h in ldsodefs.h Sergey Bugaev
2023-04-02 23:20   ` Samuel Thibault
2023-04-03  9:26     ` Sergey Bugaev
2023-04-10 21:26   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 24/34] hurd: Only check for TLS initialization inside rtld or in static builds Sergey Bugaev
2023-04-10 21:33   ` Samuel Thibault
2023-04-11 18:57   ` Samuel Thibault
2023-04-11 19:18     ` Samuel Thibault
2023-04-11 20:03     ` Samuel Thibault
2023-04-11 20:27     ` Sergey Bugaev
2023-04-11 21:23       ` Samuel Thibault
2023-04-12  8:36         ` Sergey Bugaev
2023-04-12  9:00           ` Samuel Thibault
2023-04-12 10:42             ` Sergey Bugaev
2023-04-12 10:45               ` Samuel Thibault
2023-04-12 17:18                 ` Sergey Bugaev
2023-04-12 23:46               ` Samuel Thibault
2023-04-13 10:02                 ` Sergey Bugaev
2023-04-13 10:10                   ` Samuel Thibault
2023-04-13 12:17                     ` Sergey Bugaev
2023-04-13 21:47                       ` Samuel Thibault
2023-04-13 22:21                         ` Samuel Thibault
2023-04-14  8:29                         ` Sergey Bugaev
2023-04-14  8:36                           ` Samuel Thibault
2023-04-14  8:53                             ` Sergey Bugaev
2023-04-14  9:09                               ` Samuel Thibault
2023-04-14  9:23                                 ` Sergey Bugaev
2023-04-14  9:31                                   ` Samuel Thibault
2023-04-17  7:16                               ` Samuel Thibault
2023-04-14 17:34   ` Samuel Thibault
2023-04-14 19:52     ` Sergey Bugaev
2023-03-19 15:10 ` [RFC PATCH glibc 25/34] hurd: Improve reply port handling when exiting signal handlers Sergey Bugaev
2023-04-10 22:03   ` Samuel Thibault
2023-04-11  7:44     ` Sergey Bugaev
2023-04-11 20:15       ` Samuel Thibault [this message]
2023-04-11 20:35         ` Sergey Bugaev
2023-04-12 22:54   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 26/34] hurd: Remove __hurd_local_reply_port Sergey Bugaev
2023-04-10 22:07   ` Samuel Thibault
2023-04-10 22:35     ` Samuel Thibault
2023-04-11  8:00     ` Sergey Bugaev
2023-04-11 20:18       ` Samuel Thibault
2023-04-13 11:58         ` [RFC PATCH glibc v2 " Sergey Bugaev
2023-04-13 13:12           ` Samuel Thibault
2023-04-13 13:20             ` Sergey Bugaev
2023-04-13 21:28               ` Samuel Thibault
2023-04-14 17:33           ` Samuel Thibault
2023-04-14 20:29             ` Sergey Bugaev
2023-04-15  6:45               ` Samuel Thibault
2023-04-15  7:34                 ` Sergey Bugaev
2023-04-15  7:42                   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 27/34] hurd: Don't leak __hurd_reply_port0 Sergey Bugaev
2023-04-10 22:25   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 28/34] hurd: Implement _hurd_longjmp_thread_state for x86_64 Sergey Bugaev
2023-04-02 23:23   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 29/34] hurd: Add vm_param.h " Sergey Bugaev
2023-04-02 23:24   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 30/34] hurd: Implement longjmp " Sergey Bugaev
2023-03-19 15:10 ` [RFC PATCH glibc 31/34] hurd: Microoptimize _hurd_self_sigstate () Sergey Bugaev
2023-04-02 23:26   ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 32/34] hurd: Implement sigreturn for x86_64 Sergey Bugaev
2023-04-03 11:47   ` [PATCH v2] " Sergey Bugaev
2023-03-19 15:10 ` [RFC PATCH glibc 33/34] hurd: Create abilist files for lib{mach,hurd}user Sergey Bugaev
2023-03-19 15:19   ` Samuel Thibault
2023-03-19 15:39     ` Sergey Bugaev
2023-03-19 15:43       ` Samuel Thibault
2023-03-19 15:10 ` [RFC PATCH glibc 34/34] hurd: Add expected abilist files for x86_64 Sergey Bugaev
2023-03-19 18:04   ` Florian Weimer
2023-03-19 20:14     ` [PATCH v2] " Sergey Bugaev
2023-03-20  6:30       ` Florian Weimer
2023-03-19 16:44 ` [RFC PATCH 00/34] The rest of the x86_64-gnu port Luca
2023-03-20  5:03   ` Flávio Cruz
2023-04-02 23:30 ` Samuel Thibault
2023-04-10 19:20 ` Samuel Thibault
2023-04-10 21:24   ` Sergey Bugaev
2023-04-10 21:27     ` Samuel Thibault

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