[kernel] r22027 - in dists/sid/linux/debian: . patches patches/bugfix/parisc

Mon Nov 3 23:40:50 UTC 2014

Author: benh
Date: Mon Nov  3 23:40:50 2014
New Revision: 22027

Log:
[hppa] Reduce SIGRTMIN from 37 to 32 to behave like other Linux architectures (Closes: #766635)

Added:
   dists/sid/linux/debian/patches/bugfix/parisc/parisc-reduce-sigrtmin-from-37-to-32-to-behave-like-.patch
Modified:
   dists/sid/linux/debian/changelog
   dists/sid/linux/debian/patches/series

Modified: dists/sid/linux/debian/changelog
==============================================================================

--- dists/sid/linux/debian/changelog	Mon Nov  3 23:38:23 2014	(r22026)
+++ dists/sid/linux/debian/changelog	Mon Nov  3 23:40:50 2014	(r22027)
@@ -155,6 +155,8 @@
   * [x86] Backport Thunderbolt support on Apple computers from 3.17
   * [x86] linux-image: Remove lilo from suggested boot loaders
   * [amd64] linux-image: Add grub-efi to suggested boot loaders
+  * [hppa] Reduce SIGRTMIN from 37 to 32 to behave like other Linux
+    architectures (Closes: #766635)
 
   [ Mauricio Faria de Oliveira ]
   * [ppc64el] Disable CONFIG_CMDLINE{,_BOOL} usage for setting consoles

Added: dists/sid/linux/debian/patches/bugfix/parisc/parisc-reduce-sigrtmin-from-37-to-32-to-behave-like-.patch
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ dists/sid/linux/debian/patches/bugfix/parisc/parisc-reduce-sigrtmin-from-37-to-32-to-behave-like-.patch	Mon Nov  3 23:40:50 2014	(r22027)
@@ -0,0 +1,100 @@
+From: Helge Deller <deller at gmx.de>
+Date: Fri, 10 Oct 2014 22:20:17 +0200
+Subject: parisc: Reduce SIGRTMIN from 37 to 32 to behave like other Linux
+ architectures
+Origin: https://git.kernel.org/linus/1f25df2eff5b25f52c139d3ff31bc883eee9a0ab
+Bug-Debian: https://bugs.debian.org/766635
+
+This patch reduces the value of SIGRTMIN on PARISC from 37 to 32, thus
+increasing the number of available RT signals and bring it in sync with other
+Linux architectures.
+
+Historically we wanted to natively support HP-UX 32bit binaries with the
+PA-RISC Linux port.  Because of that we carried the various available signals
+from HP-UX (e.g. SIGEMT and SIGLOST) and folded them in between the native
+Linux signals.  Although this was the right decision at that time, this
+required us to increase SIGRTMIN to at least 37 which left us with 27 (64-37)
+RT signals.
+
+Those 27 RT signals haven't been a problem in the past, but with the upcoming
+importance of systemd we now got the problem that systemd alloctes (hardcoded)
+signals up to SIGRTMIN+29 which is beyond our NSIG of 64. Because of that we
+have not been able to use systemd on the PARISC Linux port yet.
+
+Of course we could ask the systemd developers to not use those hardcoded
+values, but this change is very unlikely, esp. with PA-RISC being a niche
+architecture.
+
+The other possibility would be to increase NSIG to e.g. 128, but this would
+mean to duplicate most of the existing Linux signal handling code into the
+parisc specific Linux kernel tree which would most likely introduce lots of new
+bugs beside the code duplication.
+
+The third option is to drop some HP-UX signals and shuffle some other signals
+around to bring SIGRTMIN to 32.  This is of course an ABI change, but testing
+has shown that existing Linux installations are not visibly affected by this
+change - most likely because we move those signals around which are rarely used
+and move them to slots which haven't been used in Linux yet. In an existing
+installation I was able to exchange either the Linux kernel or glibc (or both)
+without affecting the boot process and installed applications.
+
+Dropping the HP-UX signals isn't an issue either, since support for HP-UX was
+basically dropped a few months back with Kernel 3.14 in commit
+f5a408d53edef3af07ac7697b8bc54a755628450 already, when we changed EWOULDBLOCK
+to be equal to EAGAIN.
+
+So, even if this is an ABI change, it's better to change it now and thus bring
+PARISC Linux in sync with other architectures to avoid other issues in the
+future.
+
+Signed-off-by: Helge Deller <deller at gmx.de>
+Cc: Carlos O'Donell <carlos at systemhalted.org>
+Cc: John David Anglin <dave.anglin at bell.net>
+Cc: James Bottomley <James.Bottomley at HansenPartnership.com>
+Cc: Aaro Koskinen <aaro.koskinen at iki.fi>
+Cc: PARISC Linux Kernel Mailinglist <linux-parisc at vger.kernel.org>
+Tested-by: Aaro Koskinen <aaro.koskinen at iki.fi>
+---
+ arch/parisc/include/uapi/asm/signal.h | 16 ++++++----------
+ 1 file changed, 6 insertions(+), 10 deletions(-)
+
+diff --git a/arch/parisc/include/uapi/asm/signal.h b/arch/parisc/include/uapi/asm/signal.h
+index f5645d6..10df707 100644
+--- a/arch/parisc/include/uapi/asm/signal.h
++++ b/arch/parisc/include/uapi/asm/signal.h
+@@ -8,12 +8,12 @@
+ #define SIGTRAP		 5
+ #define SIGABRT		 6
+ #define SIGIOT		 6
+-#define SIGEMT		 7
++#define SIGSTKFLT	 7
+ #define SIGFPE		 8
+ #define SIGKILL		 9
+ #define SIGBUS		10
+ #define SIGSEGV		11
+-#define SIGSYS		12 /* Linux doesn't use this */
++#define SIGXCPU		12
+ #define SIGPIPE		13
+ #define SIGALRM		14
+ #define SIGTERM		15
+@@ -32,16 +32,12 @@
+ #define SIGTTIN		27
+ #define SIGTTOU		28
+ #define SIGURG		29
+-#define SIGLOST		30 /* Linux doesn't use this either */
+-#define	SIGUNUSED	31
+-#define SIGRESERVE	SIGUNUSED
+-
+-#define SIGXCPU		33
+-#define SIGXFSZ		34
+-#define SIGSTKFLT	36
++#define SIGXFSZ		30
++#define SIGUNUSED	31
++#define SIGSYS		31 /* Linux doesn't use this */
+ 
+ /* These should not be considered constants from userland.  */
+-#define SIGRTMIN	37
++#define SIGRTMIN	32
+ #define SIGRTMAX	_NSIG /* it's 44 under HP/UX */
+ 
+ /*

Modified: dists/sid/linux/debian/patches/series
==============================================================================
--- dists/sid/linux/debian/patches/series	Mon Nov  3 23:38:23 2014	(r22026)
+++ dists/sid/linux/debian/patches/series	Mon Nov  3 23:40:50 2014	(r22027)
@@ -449,3 +449,4 @@
 features/x86/apple-tb/0029-thunderbolt-Correct-the-size-argument-to-devm_kzallo.patch
 features/x86/apple-tb/0030-thunderbolt-Use-kcalloc.patch
 features/x86/apple-tb/0031-thunderbolt-Clear-hops-before-overwriting.patch
+bugfix/parisc/parisc-reduce-sigrtmin-from-37-to-32-to-behave-like-.patch

