Hi!
On Sat, Apr 08, 2023 at 01:02:29AM +0200, Alejandro Colomar wrote:
> On 4/7/23 17:39, наб wrote:
> > @@ -99,7 +101,7 @@ interrupted by a signal handler.
> > .BR UNAME26 " (since Linux 3.1)"
> > Have
> > .BR uname (2)
> > -report a 2.6.40+ version number rather than a 3.x version number.
> > +report a 2.6.(40+x) version number rather than a MAJ.x version number.
> I prefer MAJOR.
Applied.
> > .TP
> > .BR PER_LINUX32_3GB " (since Linux 2.4)"
> > -Implies
> > +.BR PER_LINUX32 ;
> > +implies
> > .BR ADDR_LIMIT_3GB .
> I'm not sure I understand. Why on the description for tag A we
> say that B implies C? What's the relationship?
Cf. the UAPI definition:
/*
* Personality types.
*
* These go in the low byte. Avoid using the top bit, it will
* conflict with error returns.
*/
enum {
PER_LINUX = 0x0000,
PER_LINUX_32BIT = 0x0000 | ADDR_LIMIT_32BIT,
PER_LINUX_FDPIC = 0x0000 | FDPIC_FUNCPTRS,
PER_SVR4 = 0x0001 | STICKY_TIMEOUTS | MMAP_PAGE_ZERO,
PER_SVR3 = 0x0002 | STICKY_TIMEOUTS | SHORT_INODE,
PER_SCOSVR3 = 0x0003 | STICKY_TIMEOUTS |
WHOLE_SECONDS | SHORT_INODE,
PER_OSR5 = 0x0003 | STICKY_TIMEOUTS | WHOLE_SECONDS,
PER_WYSEV386 = 0x0004 | STICKY_TIMEOUTS | SHORT_INODE,
PER_ISCR4 = 0x0005 | STICKY_TIMEOUTS,
PER_BSD = 0x0006,
PER_SUNOS = 0x0006 | STICKY_TIMEOUTS,
PER_XENIX = 0x0007 | STICKY_TIMEOUTS | SHORT_INODE,
PER_LINUX32 = 0x0008,
PER_LINUX32_3GB = 0x0008 | ADDR_LIMIT_3GB,
PER_IRIX32 = 0x0009 | STICKY_TIMEOUTS,/* IRIX5 32-bit */
PER_IRIXN32 = 0x000a | STICKY_TIMEOUTS,/* IRIX6 new 32-bit */
PER_IRIX64 = 0x000b | STICKY_TIMEOUTS,/* IRIX6 64-bit */
PER_RISCOS = 0x000c,
PER_SOLARIS = 0x000d | STICKY_TIMEOUTS,
PER_UW7 = 0x000e | STICKY_TIMEOUTS | MMAP_PAGE_ZERO,
PER_OSF4 = 0x000f, /* OSF/1 v4 */
PER_HPUX = 0x0010,
PER_MASK = 0x00ff,
};
PER_LINUX is a base personality, PER_LINUX_{32BIT,FDPIC} are
PER_LINUX|ADDR_LIMIT_32BIT and PER_LINUX|FDPIC_FUNCPTRS, resp.
PER_BSD is a base personality, PER_SUNOS is PER_BSD|STICKY_TIMEOUTS.
PER_LINUX32 is a base personality, PER_LINUX32_3GB is
PER_LINUX32|ADDR_LIMIT_3GB.
I updated these all to be "Same as {base personality},
but implies {...}.". PER_SCOSVR3 has an "also", since it's the only one
where the base case PER_OSR5 has a list.
Should make more sense.
Scissor-patch below.
Best,
-- >8 --
Settle on "no effect", concretify vaguely-described behaviours;
both [to be documented]s replaced with documentation
(these match my 6.2 checkout, if there were subtleties in the history
they got lost).
Added the full system names to the PER_s that lacked them.
Didn't validate or chase down the versions except for PER_RISCOS.
Having these be sorted instead of in the original enumeration order is
really more trouble than it's worth.
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@xxxxxxxxxxxxxxxxxx>
---
man2/personality.2 | 103 +++++++++++++++++++++++++++++++--------------
1 file changed, 72 insertions(+), 31 deletions(-)
diff --git a/man2/personality.2 b/man2/personality.2
index caca709b8..d9418b38e 100644
--- a/man2/personality.2
+++ b/man2/personality.2
@@ -67,10 +67,12 @@ With this flag set, use 0xc0000000 as the offset at which to search
a virtual memory chunk on
.BR mmap (2);
otherwise use 0xffffe000.
+Applies to 32-bit x86 processes only.
.TP
.BR FDPIC_FUNCPTRS " (since Linux 2.6.11)"
User-space function pointers to signal handlers point
-(on certain architectures) to descriptors.
+to descriptors.
+Applies only to ARM if BINFMT_ELF_FDPIC and SuperH.
.TP
.BR MMAP_PAGE_ZERO " (since Linux 2.4.0)"
Map page 0 as read-only
@@ -85,7 +87,7 @@ for
.BR mmap (2).
.TP
.BR SHORT_INODE " (since Linux 2.4.0)"
-No effects(?).
+No effect.
.TP
.BR STICKY_TIMEOUTS " (since Linux 1.2.0)"
With this flag set,
@@ -99,7 +101,7 @@ interrupted by a signal handler.
.BR UNAME26 " (since Linux 3.1)"
Have
.BR uname (2)
-report a 2.6.40+ version number rather than a 3.x version number.
+report a 2.6.(40+x) version number rather than a MAJOR.x version number.
Added as a stopgap measure to support broken applications that
could not handle the
kernel version-numbering switch from Linux 2.6.x to Linux 3.x.
@@ -127,111 +129,150 @@ Implies
IRIX 6 64-bit.
Implies
.BR STICKY_TIMEOUTS ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_IRIXN32 " (since Linux 2.2)"
IRIX 6 new 32-bit.
Implies
.BR STICKY_TIMEOUTS ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_ISCR4 " (since Linux 1.2.0)"
Implies
.BR STICKY_TIMEOUTS ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_LINUX " (since Linux 1.2.0)"
Linux.
.TP
.BR PER_LINUX32 " (since Linux 2.2)"
-[To be documented.]
+.BR uname (2)
+returns the name of the 32-bit architecture in the
+.I machine
+field ("i686" instead of "x86_64", &c.).
+.IP
+Under ia64 (Itanium), processes with this personality don't have the
+O_LARGEFILE
+.BR open (2)
+flag forced.
+.IP
+Under 64-bit ARM, setting this personality is forbidden if
+.BR execve (2)ing
+a 32-bit process would also be forbidden
+(cf. the allow_mismatched_32bit_el0 kernel parameter and
+.IR Documentation/arm64/asymmetric-32bit.rst ).
.TP
.BR PER_LINUX32_3GB " (since Linux 2.4)"
-Implies
+Same as
+.BR PER_LINUX32 ,
+but implies
.BR ADDR_LIMIT_3GB .
.TP
.BR PER_LINUX_32BIT " (since Linux 2.0)"
-Implies
+Same as
+.BR PER_LINUX ,
+but implies
.BR ADDR_LIMIT_32BIT .
.TP
.BR PER_LINUX_FDPIC " (since Linux 2.6.11)"
-Implies
+Same as
+.BR PER_LINUX ,
+but implies
.BR FDPIC_FUNCPTRS .
.TP
.BR PER_OSF4 " (since Linux 2.4)"
OSF/1 v4.
-On alpha,
+.\" commit 987f20a9dcce3989e48d87cff3952c095c994445
+No effect since Linux 6.1, which removed a.out binary support.
+Before, on alpha,
.\" Following is from a comment in arch/alpha/kernel/osf_sys.c
-clear top 32 bits of iov_len in the user's buffer for
+would clear top 32 bits of iov_len in the user's buffer for
compatibility with old versions of OSF/1 where iov_len
was defined as.
.IR int .
.TP
.BR PER_OSR5 " (since Linux 2.4)"
+SCO OpenServer 5.
Implies
.B STICKY_TIMEOUTS
and
.BR WHOLE_SECONDS ;
-otherwise no effects.
+otherwise no effect.
.TP
-.BR PER_RISCOS " (since Linux 2.2)"
-[To be documented.]
+.BR PER_RISCOS " (since Linux 2.3.7; macro since Linux 2.3.13)"
+Acorn RISC OS/Arthur (MIPS).
+No effect.
+.\" commit 125ec7b4e90cbae4eed5a7ff1ee479cc331dcf3c
+Up to Linux v4.0, would set the emulation altroot to
+.I /usr/gnemul/riscos
+(cf.\&
+.BR PER_SUNOS,
+below).
+Before then, up to Linux 2.6.3, just Arthur emulation.
.TP
.BR PER_SCOSVR3 " (since Linux 1.2.0)"
-Implies
-.BR STICKY_TIMEOUTS ,
-.BR WHOLE_SECONDS ,
-and
-.BR SHORT_INODE ;
-otherwise no effects.
+SCO UNIX System V Release 3.
+Same as
+.BR PER_OSR5 ,
+but also implies
+.BR SHORT_INODE .
.TP
.BR PER_SOLARIS " (since Linux 2.4)"
+Solaris.
Implies
.BR STICKY_TIMEOUTS ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_SUNOS " (since Linux 2.4.0)"
-Implies
+Sun OS.
+Same as
+.BR PER_BSD ,
+but implies
.BR STICKY_TIMEOUTS .
-Divert library and dynamic linker searches to
+Prior to Linux 2.6.26,
+diverted library and dynamic linker searches to
.IR /usr/gnemul .
-Buggy, largely unmaintained, and almost entirely unused;
-support was removed in Linux 2.6.26.
+Buggy, largely unmaintained, and almost entirely unused.
.TP
.BR PER_SVR3 " (since Linux 1.2.0)"
+AT&T UNIX System V Release 3.
Implies
.B STICKY_TIMEOUTS
and
.BR SHORT_INODE ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_SVR4 " (since Linux 1.2.0)"
+AT&T UNIX System V Release 4.
Implies
.B STICKY_TIMEOUTS
and
.BR MMAP_PAGE_ZERO ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_UW7 " (since Linux 2.4)"
+UnixWare 7.
Implies
.B STICKY_TIMEOUTS
and
.BR MMAP_PAGE_ZERO ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_WYSEV386 " (since Linux 1.2.0)"
+WYSE UNIX System V/386.
Implies
.B STICKY_TIMEOUTS
and
.BR SHORT_INODE ;
-otherwise no effects.
+otherwise no effect.
.TP
.BR PER_XENIX " (since Linux 1.2.0)"
+XENIX.
Implies
.B STICKY_TIMEOUTS
and
.BR SHORT_INODE ;
-otherwise no effects.
+otherwise no effect.
.SH RETURN VALUE
On success, the previous
.I persona
--
2.30.2
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