Revision 706a1ea65e6faaf853427a0e931f59d604dd45e3 authored by Linus Torvalds on 23 August 2018, 21:55:01 UTC, committed by Linus Torvalds on 23 August 2018, 21:55:01 UTC
Merge fixes for missing TLB shootdowns.

This fixes a couple of cases that involved us possibly freeing page
table structures before the required TLB shootdown had been done.

There are a few cleanup patches to make the code easier to follow, and
to avoid some of the more problematic cases entirely when not necessary.

To make this easier for backports, it undoes the recent lazy TLB
patches, because the cleanups and fixes are more important, and Rik is
ok with re-doing them later when things have calmed down.

The missing TLB flush was only delayed, and the wrong ordering only
happened under memory pressure (and in theory under a couple of other
fairly theoretical situations), so this may have been all very unlikely
to have hit people in practice.

But getting the TLB shootdown wrong is _so_ hard to debug and see that I
consider this a crticial fix.

Many thanks to Jann Horn for having debugged this.

* tlb-fixes:
  x86/mm: Only use tlb_remove_table() for paravirt
  mm: mmu_notifier fix for tlb_end_vma
  mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREE
  mm/tlb: Remove tlb_remove_table() non-concurrent condition
  mm: move tlb_table_flush to tlb_flush_mmu_free
  x86/mm/tlb: Revert the recent lazy TLB patches
2 parent s d40acad + 48a8b97
Raw File
Makefile
# SPDX-License-Identifier: GPL-2.0
#
# Makefile for the linux kernel signature checking certificates.
#

obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o
ifneq ($(CONFIG_SYSTEM_BLACKLIST_HASH_LIST),"")
obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist_hashes.o
else
obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist_nohashes.o
endif

ifeq ($(CONFIG_SYSTEM_TRUSTED_KEYRING),y)

$(eval $(call config_filename,SYSTEM_TRUSTED_KEYS))

# GCC doesn't include .incbin files in -MD generated dependencies (PR#66871)
$(obj)/system_certificates.o: $(obj)/x509_certificate_list

# Cope with signing_key.x509 existing in $(srctree) not $(objtree)
AFLAGS_system_certificates.o := -I$(srctree)

quiet_cmd_extract_certs  = EXTRACT_CERTS   $(patsubst "%",%,$(2))
      cmd_extract_certs  = scripts/extract-cert $(2) $@ || ( rm $@; exit 1)

targets += x509_certificate_list
$(obj)/x509_certificate_list: scripts/extract-cert $(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(SYSTEM_TRUSTED_KEYS_FILENAME) FORCE
	$(call if_changed,extract_certs,$(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(CONFIG_SYSTEM_TRUSTED_KEYS))
endif # CONFIG_SYSTEM_TRUSTED_KEYRING

clean-files := x509_certificate_list .x509.list

ifeq ($(CONFIG_MODULE_SIG),y)
###############################################################################
#
# If module signing is requested, say by allyesconfig, but a key has not been
# supplied, then one will need to be generated to make sure the build does not
# fail and that the kernel may be used afterwards.
#
###############################################################################
ifndef CONFIG_MODULE_SIG_HASH
$(error Could not determine digest type to use from kernel config)
endif

redirect_openssl	= 2>&1
quiet_redirect_openssl	= 2>&1
silent_redirect_openssl = 2>/dev/null

# We do it this way rather than having a boolean option for enabling an
# external private key, because 'make randconfig' might enable such a
# boolean option and we unfortunately can't make it depend on !RANDCONFIG.
ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem")
$(obj)/signing_key.pem: $(obj)/x509.genkey
	@$(kecho) "###"
	@$(kecho) "### Now generating an X.509 key pair to be used for signing modules."
	@$(kecho) "###"
	@$(kecho) "### If this takes a long time, you might wish to run rngd in the"
	@$(kecho) "### background to keep the supply of entropy topped up.  It"
	@$(kecho) "### needs to be run as root, and uses a hardware random"
	@$(kecho) "### number generator if one is available."
	@$(kecho) "###"
	$(Q)openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
		-batch -x509 -config $(obj)/x509.genkey \
		-outform PEM -out $(obj)/signing_key.pem \
		-keyout $(obj)/signing_key.pem \
		$($(quiet)redirect_openssl)
	@$(kecho) "###"
	@$(kecho) "### Key pair generated."
	@$(kecho) "###"

$(obj)/x509.genkey:
	@$(kecho) Generating X.509 key generation config
	@echo  >$@ "[ req ]"
	@echo >>$@ "default_bits = 4096"
	@echo >>$@ "distinguished_name = req_distinguished_name"
	@echo >>$@ "prompt = no"
	@echo >>$@ "string_mask = utf8only"
	@echo >>$@ "x509_extensions = myexts"
	@echo >>$@
	@echo >>$@ "[ req_distinguished_name ]"
	@echo >>$@ "#O = Unspecified company"
	@echo >>$@ "CN = Build time autogenerated kernel key"
	@echo >>$@ "#emailAddress = unspecified.user@unspecified.company"
	@echo >>$@
	@echo >>$@ "[ myexts ]"
	@echo >>$@ "basicConstraints=critical,CA:FALSE"
	@echo >>$@ "keyUsage=digitalSignature"
	@echo >>$@ "subjectKeyIdentifier=hash"
	@echo >>$@ "authorityKeyIdentifier=keyid"
endif # CONFIG_MODULE_SIG_KEY

$(eval $(call config_filename,MODULE_SIG_KEY))

# If CONFIG_MODULE_SIG_KEY isn't a PKCS#11 URI, depend on it
ifeq ($(patsubst pkcs11:%,%,$(firstword $(MODULE_SIG_KEY_FILENAME))),$(firstword $(MODULE_SIG_KEY_FILENAME)))
X509_DEP := $(MODULE_SIG_KEY_SRCPREFIX)$(MODULE_SIG_KEY_FILENAME)
endif

# GCC PR#66871 again.
$(obj)/system_certificates.o: $(obj)/signing_key.x509

targets += signing_key.x509
$(obj)/signing_key.x509: scripts/extract-cert $(X509_DEP) FORCE
	$(call if_changed,extract_certs,$(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY))
endif # CONFIG_MODULE_SIG
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