Go to file
Nicholas Piggin 1f9bb31e58 selftests/powerpc: Add FPU denormal test
Add a testcase that tries to trigger the FPU denormal exception on
Power8 or earlier CPUs.

Prior to commit 4557ac6b34 ("powerpc/64s/exception: Fix 0x1500
interrupt handler crash") this would trigger a crash such as:

  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV
  Modules linked in: iptable_mangle xt_MASQUERADE iptable_nat nf_nat xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ipt_REJECT nf_reject_ipv4 xt_tcpudp tun bridge stp llc ip6table_filter ip6_tables iptable_filter fuse kvm_hv binfmt_misc squashfs mlx4_ib ib_uverbs dm_multipath scsi_dh_rdac scsi_dh_alua ib_core mlx4_en sr_mod cdrom bnx2x lpfc mlx4_core crc_t10dif scsi_transport_fc sg mdio vmx_crypto crct10dif_vpmsum leds_powernv powernv_rng rng_core led_class powernv_op_panel sunrpc ip_tables x_tables autofs4
  CPU: 159 PID: 6854 Comm: fpu_denormal Not tainted 5.8.0-rc2-gcc-8.2.0-00092-g4ec7aaab0828 #192
  NIP:  c0000000000100ec LR: c00000000001b85c CTR: 0000000000000000
  REGS: c000001dd818f770 TRAP: 1500   Not tainted  (5.8.0-rc2-gcc-8.2.0-00092-g4ec7aaab0828)
  MSR:  900000000290b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 24002884  XER: 20000000
  CFAR: c00000000001005c IRQMASK: 1
  GPR00: c00000000001c4c8 c000001dd818fa00 c00000000171c200 c000001dd8101570
  GPR04: 0000000000000000 c000001dd818fe90 c000001dd8101590 000000000000001d
  GPR08: 0000000000000010 0000000000002000 c000001dd818fe90 fffffffffc48ac60
  GPR12: 0000000000002200 c000001ffff4f480 0000000000000000 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 00007fffab225b40 0000000000000001 c000000001757168
  GPR24: c000001dd8101570 c0000018027b00f0 c000001dd8101570 c000000001496098
  GPR28: c00000000174ad05 c000001dd8100000 c000001dd8100000 c000001dd8100000
  NIP save_fpu+0xa8/0x2ac
  LR  __giveup_fpu+0x2c/0xd0
  Call Trace:
    0xc000001dd818fa80 (unreliable)
    giveup_all+0x118/0x120
    __switch_to+0x124/0x6c0
    __schedule+0x390/0xaf0
    do_task_dead+0x70/0x80
    do_exit+0x8fc/0xe10
    do_group_exit+0x64/0xd0
    sys_exit_group+0x24/0x30
    system_call_exception+0x164/0x270
    system_call_common+0xf0/0x278

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of fix patch, add oops log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200708074942.1713396-1-npiggin@gmail.com
2020-07-15 12:02:20 +10:00
Documentation ocxl: control via sysfs whether the FPGA is reloaded on a link reset 2020-07-15 11:07:19 +10:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
arch powerpc/64/signal: Balance return predictor stack in signal trampoline 2020-07-15 11:08:27 +10:00
block block-5.8-2020-06-19 2020-06-19 13:11:26 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto crypto: drbg - always try to free Jitter RNG instance 2020-06-15 17:38:54 +10:00
drivers cpuidle/powernv : Remove dead code block 2020-07-15 11:07:20 +10:00
fs A few fixes and small cleanups for tracing: 2020-06-20 13:17:47 -07:00
include ocxl: control via sysfs whether the FPGA is reloaded on a link reset 2020-07-15 11:07:19 +10:00
init Kbuild updates for v5.8 (2nd) 2020-06-13 13:29:16 -07:00
ipc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
kernel A few fixes and small cleanups for tracing: 2020-06-20 13:17:47 -07:00
lib Kbuild fixes for v5.8 2020-06-21 12:44:52 -07:00
mm powerpc fixes for 5.8 #3 2020-06-21 10:02:53 -07:00
net An important follow-up for replica reads support that went into -rc1 2020-06-19 12:25:04 -07:00
samples Kbuild fixes for v5.8 2020-06-21 12:44:52 -07:00
scripts Kbuild fixes for v5.8 2020-06-21 12:44:52 -07:00
security selinux/stable-5.8 PR 20200621 2020-06-21 15:41:24 -07:00
sound ASoC: SOF: Replace zero-length array with flexible-array 2020-06-15 23:08:32 -05:00
tools selftests/powerpc: Add FPU denormal test 2020-07-15 12:02:20 +10:00
usr bpfilter: match bit size of bpfilter_umh to that of the kernel 2020-05-17 18:52:01 +09:00
virt MIPS: 2020-06-12 11:05:52 -07:00
.clang-format block: add bio_for_each_bvec_all() 2020-05-25 11:25:24 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore modpost: generate vmlinux.symvers and reuse it for the second modpost 2020-06-06 23:38:12 +09:00
.mailmap A fair amount of stuff this time around, dominated by yet another massive 2020-06-01 15:45:27 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS mailmap: change email for Ricardo Ribalda 2020-05-25 18:59:59 -06:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: Remove self from powerpc EEH 2020-07-15 11:07:19 +10:00
Makefile Linux 5.8-rc2 2020-06-21 15:45:29 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.