Andy Lutomirski ff17bbe0bb x86/vdso: Prevent segfaults due to hoisted vclock reads ... GCC 5.5.0 sometimes cleverly hoists reads of the pvclock and/or hvclock pages before the vclock mode checks. This creates a path through vclock_gettime() in which no vclock is enabled at all (due to disabled TSC on old CPUs, for example) but the pvclock or hvclock page nevertheless read. This will segfault on bare metal. This fixes commit 459e3a2153 ("gcc-9: properly declare the {pv,hv}clock_page storage") in the sense that, before that commit, GCC didn't seem to generate the offending code. There was nothing wrong with that commit per se, and -stable maintainers should backport this to all supported kernels regardless of whether the offending commit was present, since the same crash could just as easily be triggered by the phase of the moon. On GCC 9.1.1, this doesn't seem to affect the generated code at all, so I'm not too concerned about performance regressions from this fix. Cc: stable@vger.kernel.org Cc: x86@kernel.org Cc: Borislav Petkov <bp@alien8.de> Reported-by: Duncan Roe <duncan_roe@optusnet.com.au> Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2019-06-21 13:31:52 -07:00
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syscalls	uapi, x86: Fix the syscall numbering of the mount API syscalls [ver #2]	2019-05-16 12:23:45 -04:00
vdso	x86/vdso: Prevent segfaults due to hoisted vclock reads	2019-06-21 13:31:52 -07:00
vsyscall	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 180	2019-05-30 11:29:20 -07:00
calling.h	jump_label: move 'asm goto' support test to Kconfig	2019-01-06 09:46:51 +09:00
common.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257	2019-06-05 17:30:27 +02:00
entry_32.S	Merge branch 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-05-06 15:55:15 -07:00
entry_64_compat.S	x86/entry/64/compat: Fix stack switching for XEN PV	2019-01-18 00:39:33 +01:00
entry_64.S	The major changes in this tracing update includes:	2019-05-15 16:05:47 -07:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
syscall_32.c	syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64	2018-04-05 16:59:38 +02:00
syscall_64.c	syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64	2018-04-05 16:59:38 +02:00
thunk_32.S	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 474	2019-06-19 17:09:11 +02:00
thunk_64.S	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 474	2019-06-19 17:09:11 +02:00