From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Catalin Marinas <catalin.marinas@arm.com>,
James Morse <james.morse@arm.com>
Subject: [PATCH 4.14 20/27] arm64: entry: Add macro for reading symbol addresses from the trampoline
Date: Fri, 1 Apr 2022 08:36:30 +0200 [thread overview]
Message-ID: <20220401063624.805192741@linuxfoundation.org> (raw)
In-Reply-To: <20220401063624.232282121@linuxfoundation.org>
From: James Morse <james.morse@arm.com>
commit b28a8eebe81c186fdb1a0078263b30576c8e1f42 upstream.
The trampoline code needs to use the address of symbols in the wider
kernel, e.g. vectors. PC-relative addressing wouldn't work as the
trampoline code doesn't run at the address the linker expected.
tramp_ventry uses a literal pool, unless CONFIG_RANDOMIZE_BASE is
set, in which case it uses the data page as a literal pool because
the data page can be unmapped when running in user-space, which is
required for CPUs vulnerable to meltdown.
Pull this logic out as a macro, instead of adding a third copy
of it.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ Removed SDEI for stable backport ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm64/kernel/entry.S | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -1022,6 +1022,15 @@ alternative_else_nop_endif
sub \dst, \dst, PAGE_SIZE
.endm
+ .macro tramp_data_read_var dst, var
+#ifdef CONFIG_RANDOMIZE_BASE
+ tramp_data_page \dst
+ add \dst, \dst, #:lo12:__entry_tramp_data_\var
+ ldr \dst, [\dst]
+#else
+ ldr \dst, =\var
+#endif
+ .endm
#define BHB_MITIGATION_NONE 0
#define BHB_MITIGATION_LOOP 1
@@ -1052,13 +1061,8 @@ alternative_else_nop_endif
b .
2:
tramp_map_kernel x30
-#ifdef CONFIG_RANDOMIZE_BASE
- tramp_data_page x30
alternative_insn isb, nop, ARM64_WORKAROUND_QCOM_FALKOR_E1003
- ldr x30, [x30]
-#else
- ldr x30, =vectors
-#endif
+ tramp_data_read_var x30, vectors
prfm plil1strm, [x30, #(1b - \vector_start)]
msr vbar_el1, x30
isb
@@ -1138,7 +1142,12 @@ END(tramp_exit_compat)
.align PAGE_SHIFT
.globl __entry_tramp_data_start
__entry_tramp_data_start:
+__entry_tramp_data_vectors:
.quad vectors
+#ifdef CONFIG_ARM_SDE_INTERFACE
+__entry_tramp_data___sdei_asm_trampoline_next_handler:
+ .quad __sdei_asm_handler
+#endif /* CONFIG_ARM_SDE_INTERFACE */
.popsection // .rodata
#endif /* CONFIG_RANDOMIZE_BASE */
#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
next prev parent reply other threads:[~2022-04-01 6:38 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-01 6:36 [PATCH 4.14 00/27] 4.14.275-rc1 review Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 01/27] arm64: arch_timer: Add workaround for ARM erratum 1188873 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 02/27] arm64: arch_timer: avoid unused function warning Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 03/27] arm64: Add silicon-errata.txt entry for ARM erratum 1188873 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 04/27] arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 05/27] arm64: Add part number for Neoverse N1 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 06/27] arm64: Add part number for Arm Cortex-A77 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 07/27] arm64: Add Neoverse-N2, Cortex-A710 CPU part definition Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 08/27] arm64: Add Cortex-X2 " Greg Kroah-Hartman
2022-04-01 6:36 ` Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 09/27] arm64: entry.S: Add ventry overflow sanity checks Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 10/27] arm64: entry: Make the trampoline cleanup optional Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 11/27] arm64: entry: Free up another register on kptis tramp_exit path Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 12/27] arm64: entry: Move the trampoline data page before the text page Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 13/27] arm64: entry: Allow tramp_alias to access symbols after the 4K boundary Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 14/27] arm64: entry: Dont assume tramp_vectors is the start of the vectors Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 15/27] arm64: entry: Move trampoline macros out of ifdefd section Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 16/27] arm64: entry: Make the kpti trampolines kpti sequence optional Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 17/27] arm64: entry: Allow the trampoline text to occupy multiple pages Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 18/27] arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 19/27] arm64: entry: Add vectors that have the bhb mitigation sequences Greg Kroah-Hartman
2022-04-01 6:36 ` Greg Kroah-Hartman [this message]
2022-04-01 6:36 ` [PATCH 4.14 21/27] arm64: Add percpu vectors for EL1 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 22/27] arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 23/27] KVM: arm64: Add templates for BHB mitigation sequences Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 24/27] arm64: Mitigate spectre style branch history side channels Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 25/27] KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 26/27] arm64: add ID_AA64ISAR2_EL1 sys register Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 27/27] arm64: Use the clearbhb instruction in mitigations Greg Kroah-Hartman
2022-04-01 10:43 ` [PATCH 4.14 00/27] 4.14.275-rc1 review Guenter Roeck
2022-04-01 18:26 ` Naresh Kamboju
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220401063624.805192741@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=catalin.marinas@arm.com \
--cc=james.morse@arm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.