On Fri, Apr 5, 2024 at 12:34 AM Ramon de C Valle <rcvalle(a)google.com> wrote:
>
> Sorry about that, I should've done this already. In addition to the link you added above, here's a tracking issue for KCFI support for Rust:
> https://github.com/rust-lang/rust/issues/123479
No worries! Thanks for taking the time creating the new tracking issue
-- linked now from our issue #2.
I also linked your update here and noted the benchmarking needs /
regressions report request too.
Cheers,
Miguel
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 4535e1a4174c4111d92c5a9a21e542d232e0fcaa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024033030-steam-implosion-5c12@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4535e1a4174c4111d92c5a9a21e542d232e0fcaa Mon Sep 17 00:00:00 2001
From: "Borislav Petkov (AMD)" <bp(a)alien8.de>
Date: Thu, 28 Mar 2024 13:59:05 +0100
Subject: [PATCH] x86/bugs: Fix the SRSO mitigation on Zen3/4
The original version of the mitigation would patch in the calls to the
untraining routines directly. That is, the alternative() in UNTRAIN_RET
will patch in the CALL to srso_alias_untrain_ret() directly.
However, even if commit e7c25c441e9e ("x86/cpu: Cleanup the untrain
mess") meant well in trying to clean up the situation, due to micro-
architectural reasons, the untraining routine srso_alias_untrain_ret()
must be the target of a CALL instruction and not of a JMP instruction as
it is done now.
Reshuffle the alternative macros to accomplish that.
Fixes: e7c25c441e9e ("x86/cpu: Cleanup the untrain mess")
Signed-off-by: Borislav Petkov (AMD) <bp(a)alien8.de>
Reviewed-by: Ingo Molnar <mingo(a)kernel.org>
Cc: stable(a)kernel.org
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h
index 076bf8dee702..25466c4d2134 100644
--- a/arch/x86/include/asm/asm-prototypes.h
+++ b/arch/x86/include/asm/asm-prototypes.h
@@ -14,6 +14,7 @@
#include <asm/asm.h>
#include <asm/fred.h>
#include <asm/gsseg.h>
+#include <asm/nospec-branch.h>
#ifndef CONFIG_X86_CMPXCHG64
extern void cmpxchg8b_emu(void);
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index fc3a8a3c7ffe..170c89ed22fc 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -262,11 +262,20 @@
.Lskip_rsb_\@:
.endm
+/*
+ * The CALL to srso_alias_untrain_ret() must be patched in directly at
+ * the spot where untraining must be done, ie., srso_alias_untrain_ret()
+ * must be the target of a CALL instruction instead of indirectly
+ * jumping to a wrapper which then calls it. Therefore, this macro is
+ * called outside of __UNTRAIN_RET below, for the time being, before the
+ * kernel can support nested alternatives with arbitrary nesting.
+ */
+.macro CALL_UNTRAIN_RET
#if defined(CONFIG_MITIGATION_UNRET_ENTRY) || defined(CONFIG_MITIGATION_SRSO)
-#define CALL_UNTRAIN_RET "call entry_untrain_ret"
-#else
-#define CALL_UNTRAIN_RET ""
+ ALTERNATIVE_2 "", "call entry_untrain_ret", X86_FEATURE_UNRET, \
+ "call srso_alias_untrain_ret", X86_FEATURE_SRSO_ALIAS
#endif
+.endm
/*
* Mitigate RETBleed for AMD/Hygon Zen uarch. Requires KERNEL CR3 because the
@@ -282,8 +291,8 @@
.macro __UNTRAIN_RET ibpb_feature, call_depth_insns
#if defined(CONFIG_MITIGATION_RETHUNK) || defined(CONFIG_MITIGATION_IBPB_ENTRY)
VALIDATE_UNRET_END
- ALTERNATIVE_3 "", \
- CALL_UNTRAIN_RET, X86_FEATURE_UNRET, \
+ CALL_UNTRAIN_RET
+ ALTERNATIVE_2 "", \
"call entry_ibpb", \ibpb_feature, \
__stringify(\call_depth_insns), X86_FEATURE_CALL_DEPTH
#endif
@@ -342,6 +351,8 @@ extern void retbleed_return_thunk(void);
static inline void retbleed_return_thunk(void) {}
#endif
+extern void srso_alias_untrain_ret(void);
+
#ifdef CONFIG_MITIGATION_SRSO
extern void srso_return_thunk(void);
extern void srso_alias_return_thunk(void);
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index 721b528da9ac..02cde194a99e 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -163,6 +163,7 @@ SYM_CODE_START_NOALIGN(srso_alias_untrain_ret)
lfence
jmp srso_alias_return_thunk
SYM_FUNC_END(srso_alias_untrain_ret)
+__EXPORT_THUNK(srso_alias_untrain_ret)
.popsection
.pushsection .text..__x86.rethunk_safe
@@ -224,10 +225,12 @@ SYM_CODE_START(srso_return_thunk)
SYM_CODE_END(srso_return_thunk)
#define JMP_SRSO_UNTRAIN_RET "jmp srso_untrain_ret"
-#define JMP_SRSO_ALIAS_UNTRAIN_RET "jmp srso_alias_untrain_ret"
#else /* !CONFIG_MITIGATION_SRSO */
+/* Dummy for the alternative in CALL_UNTRAIN_RET. */
+SYM_CODE_START(srso_alias_untrain_ret)
+ RET
+SYM_FUNC_END(srso_alias_untrain_ret)
#define JMP_SRSO_UNTRAIN_RET "ud2"
-#define JMP_SRSO_ALIAS_UNTRAIN_RET "ud2"
#endif /* CONFIG_MITIGATION_SRSO */
#ifdef CONFIG_MITIGATION_UNRET_ENTRY
@@ -319,9 +322,7 @@ SYM_FUNC_END(retbleed_untrain_ret)
#if defined(CONFIG_MITIGATION_UNRET_ENTRY) || defined(CONFIG_MITIGATION_SRSO)
SYM_FUNC_START(entry_untrain_ret)
- ALTERNATIVE_2 JMP_RETBLEED_UNTRAIN_RET, \
- JMP_SRSO_UNTRAIN_RET, X86_FEATURE_SRSO, \
- JMP_SRSO_ALIAS_UNTRAIN_RET, X86_FEATURE_SRSO_ALIAS
+ ALTERNATIVE JMP_RETBLEED_UNTRAIN_RET, JMP_SRSO_UNTRAIN_RET, X86_FEATURE_SRSO
SYM_FUNC_END(entry_untrain_ret)
__EXPORT_THUNK(entry_untrain_ret)
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x cbc17e7802f5de37c7c262204baadfad3f7f99e5
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040527-action-late-9749@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From cbc17e7802f5de37c7c262204baadfad3f7f99e5 Mon Sep 17 00:00:00 2001
From: Wei Fang <wei.fang(a)nxp.com>
Date: Thu, 28 Mar 2024 15:59:29 +0000
Subject: [PATCH] net: fec: Set mac_managed_pm during probe
Setting mac_managed_pm during interface up is too late.
In situations where the link is not brought up yet and the system suspends
the regular PHY power management will run. Since the FEC ETHEREN control
bit is cleared (automatically) on suspend the controller is off in resume.
When the regular PHY power management resume path runs in this context it
will write to the MII_DATA register but nothing will be transmitted on the
MDIO bus.
This can be observed by the following log:
fec 5b040000.ethernet eth0: MDIO read timeout
Microchip LAN87xx T1 5b040000.ethernet-1:04: PM: dpm_run_callback(): mdio_bus_phy_resume+0x0/0xc8 returns -110
Microchip LAN87xx T1 5b040000.ethernet-1:04: PM: failed to resume: error -110
The data written will however remain in the MII_DATA register.
When the link later is set to administrative up it will trigger a call to
fec_restart() which will restore the MII_SPEED register. This triggers the
quirk explained in f166f890c8f0 ("net: ethernet: fec: Replace interrupt
driven MDIO with polled IO") causing an extra MII_EVENT.
This extra event desynchronizes all the MDIO register reads, causing them
to complete too early. Leading all reads to read as 0 because
fec_enet_mdio_wait() returns too early.
When a Microchip LAN8700R PHY is connected to the FEC, the 0 reads causes
the PHY to be initialized incorrectly and the PHY will not transmit any
ethernet signal in this state. It cannot be brought out of this state
without a power cycle of the PHY.
Fixes: 557d5dc83f68 ("net: fec: use mac-managed PHY PM")
Closes: https://lore.kernel.org/netdev/1f45bdbe-eab1-4e59-8f24-add177590d27@actia.s…
Signed-off-by: Wei Fang <wei.fang(a)nxp.com>
[jernberg: commit message]
Signed-off-by: John Ernberg <john.ernberg(a)actia.se>
Link: https://lore.kernel.org/r/20240328155909.59613-2-john.ernberg@actia.se
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index d7693fdf640d..8bd213da8fb6 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2454,8 +2454,6 @@ static int fec_enet_mii_probe(struct net_device *ndev)
fep->link = 0;
fep->full_duplex = 0;
- phy_dev->mac_managed_pm = true;
-
phy_attached_info(phy_dev);
return 0;
@@ -2467,10 +2465,12 @@ static int fec_enet_mii_init(struct platform_device *pdev)
struct net_device *ndev = platform_get_drvdata(pdev);
struct fec_enet_private *fep = netdev_priv(ndev);
bool suppress_preamble = false;
+ struct phy_device *phydev;
struct device_node *node;
int err = -ENXIO;
u32 mii_speed, holdtime;
u32 bus_freq;
+ int addr;
/*
* The i.MX28 dual fec interfaces are not equal.
@@ -2584,6 +2584,13 @@ static int fec_enet_mii_init(struct platform_device *pdev)
goto err_out_free_mdiobus;
of_node_put(node);
+ /* find all the PHY devices on the bus and set mac_managed_pm to true */
+ for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
+ phydev = mdiobus_get_phy(fep->mii_bus, addr);
+ if (phydev)
+ phydev->mac_managed_pm = true;
+ }
+
mii_cnt++;
/* save fec0 mii_bus */
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x cbc17e7802f5de37c7c262204baadfad3f7f99e5
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040525-buccaneer-rehab-aa0f@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From cbc17e7802f5de37c7c262204baadfad3f7f99e5 Mon Sep 17 00:00:00 2001
From: Wei Fang <wei.fang(a)nxp.com>
Date: Thu, 28 Mar 2024 15:59:29 +0000
Subject: [PATCH] net: fec: Set mac_managed_pm during probe
Setting mac_managed_pm during interface up is too late.
In situations where the link is not brought up yet and the system suspends
the regular PHY power management will run. Since the FEC ETHEREN control
bit is cleared (automatically) on suspend the controller is off in resume.
When the regular PHY power management resume path runs in this context it
will write to the MII_DATA register but nothing will be transmitted on the
MDIO bus.
This can be observed by the following log:
fec 5b040000.ethernet eth0: MDIO read timeout
Microchip LAN87xx T1 5b040000.ethernet-1:04: PM: dpm_run_callback(): mdio_bus_phy_resume+0x0/0xc8 returns -110
Microchip LAN87xx T1 5b040000.ethernet-1:04: PM: failed to resume: error -110
The data written will however remain in the MII_DATA register.
When the link later is set to administrative up it will trigger a call to
fec_restart() which will restore the MII_SPEED register. This triggers the
quirk explained in f166f890c8f0 ("net: ethernet: fec: Replace interrupt
driven MDIO with polled IO") causing an extra MII_EVENT.
This extra event desynchronizes all the MDIO register reads, causing them
to complete too early. Leading all reads to read as 0 because
fec_enet_mdio_wait() returns too early.
When a Microchip LAN8700R PHY is connected to the FEC, the 0 reads causes
the PHY to be initialized incorrectly and the PHY will not transmit any
ethernet signal in this state. It cannot be brought out of this state
without a power cycle of the PHY.
Fixes: 557d5dc83f68 ("net: fec: use mac-managed PHY PM")
Closes: https://lore.kernel.org/netdev/1f45bdbe-eab1-4e59-8f24-add177590d27@actia.s…
Signed-off-by: Wei Fang <wei.fang(a)nxp.com>
[jernberg: commit message]
Signed-off-by: John Ernberg <john.ernberg(a)actia.se>
Link: https://lore.kernel.org/r/20240328155909.59613-2-john.ernberg@actia.se
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index d7693fdf640d..8bd213da8fb6 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2454,8 +2454,6 @@ static int fec_enet_mii_probe(struct net_device *ndev)
fep->link = 0;
fep->full_duplex = 0;
- phy_dev->mac_managed_pm = true;
-
phy_attached_info(phy_dev);
return 0;
@@ -2467,10 +2465,12 @@ static int fec_enet_mii_init(struct platform_device *pdev)
struct net_device *ndev = platform_get_drvdata(pdev);
struct fec_enet_private *fep = netdev_priv(ndev);
bool suppress_preamble = false;
+ struct phy_device *phydev;
struct device_node *node;
int err = -ENXIO;
u32 mii_speed, holdtime;
u32 bus_freq;
+ int addr;
/*
* The i.MX28 dual fec interfaces are not equal.
@@ -2584,6 +2584,13 @@ static int fec_enet_mii_init(struct platform_device *pdev)
goto err_out_free_mdiobus;
of_node_put(node);
+ /* find all the PHY devices on the bus and set mac_managed_pm to true */
+ for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
+ phydev = mdiobus_get_phy(fep->mii_bus, addr);
+ if (phydev)
+ phydev->mac_managed_pm = true;
+ }
+
mii_cnt++;
/* save fec0 mii_bus */