The JIT compile of ldimm instructions can be anywhere between 1-5
instructions long depending on the value being loaded.
arch_bpf_trampoline_size() provides JIT size of the BPF trampoline
before the buffer for JIT'ing it is allocated. BPF trampoline JIT
code has ldimm instructions that need to load the value of pointer
to struct bpf_tramp_image. But this pointer value is not same while
calling arch_bpf_trampoline_size() & arch_prepare_bpf_trampoline().
So, the size arrived at using arch_bpf_trampoline_size() can vary
from the size needed in arch_prepare_bpf_trampoline(). When the
number of ldimm instructions emitted in arch_bpf_trampoline_size()
is less than the number of ldimm instructions emitted during the
actual JIT compile of trampoline, the below warning is produced:
WARNING: CPU: 8 PID: 204190 at arch/powerpc/net/bpf_jit_comp.c:981 __arch_prepare_bpf_trampoline.isra.0+0xd2c/0xdcc
which is:
/* Make sure the trampoline generation logic doesn't overflow */
if (image && WARN_ON_ONCE(&image[ctx->idx] >
(u32 *)rw_image_end - BPF_INSN_SAFETY)) {
Pass NULL as the first argument to __arch_prepare_bpf_trampoline()
call from arch_bpf_trampoline_size() function, to differentiate it
from how arch_prepare_bpf_trampoline() calls it and ensure maximum
possible instructions are emitted in arch_bpf_trampoline_size() for
ldimm instructions that load a different value during the actual JIT
compile of BPF trampoline.
Fixes: d243b62b7bd3 ("powerpc64/bpf: Add support for bpf trampolines")
Reported-by: Venkat Rao Bagalkote <venkat88(a)linux.ibm.com>
Closes: https://lore.kernel.org/all/6168bfc8-659f-4b5a-a6fb-90a916dde3b3@linux.ibm.…
Cc: stable(a)vger.kernel.org # v6.13+
Signed-off-by: Hari Bathini <hbathini(a)linux.ibm.com>
---
arch/powerpc/net/bpf_jit_comp.c | 31 ++++++++++++++++++++++++-------
1 file changed, 24 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 2991bb171a9b..49d7e9a8d17c 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -686,7 +686,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
* [ ] --
* LR save area [ r0 save (64-bit) ] | header
* [ r0 save (32-bit) ] |
- * dummy frame for unwind [ back chain 1 ] --
+ /* dummy frame for unwind [ back chain 1 ] --
* [ padding ] align stack frame
* r4_off [ r4 (tailcallcnt) ] optional - 32-bit powerpc
* alt_lr_off [ real lr (ool stub)] optional - actual lr
@@ -833,7 +833,12 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
EMIT(PPC_RAW_STL(_R26, _R1, nvr_off + SZL));
if (flags & BPF_TRAMP_F_CALL_ORIG) {
- PPC_LI_ADDR(_R3, (unsigned long)im);
+ /*
+ * Emit maximum possible instructions while getting the size of
+ * bpf trampoline to ensure trampoline JIT code doesn't overflow.
+ */
+ PPC_LI_ADDR(_R3, im ? (unsigned long)im :
+ (unsigned long)(~(1UL << (BITS_PER_LONG - 1))));
ret = bpf_jit_emit_func_call_rel(image, ro_image, ctx,
(unsigned long)__bpf_tramp_enter);
if (ret)
@@ -889,7 +894,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
bpf_trampoline_restore_tail_call_cnt(image, ctx, func_frame_offset, r4_off);
/* Reserve space to patch branch instruction to skip fexit progs */
- im->ip_after_call = &((u32 *)ro_image)[ctx->idx];
+ if (im)
+ im->ip_after_call = &((u32 *)ro_image)[ctx->idx];
EMIT(PPC_RAW_NOP());
}
@@ -912,8 +918,14 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
}
if (flags & BPF_TRAMP_F_CALL_ORIG) {
- im->ip_epilogue = &((u32 *)ro_image)[ctx->idx];
- PPC_LI_ADDR(_R3, im);
+ if (im)
+ im->ip_epilogue = &((u32 *)ro_image)[ctx->idx];
+ /*
+ * Emit maximum possible instructions while getting the size of
+ * bpf trampoline to ensure trampoline JIT code doesn't overflow.
+ */
+ PPC_LI_ADDR(_R3, im ? (unsigned long)im :
+ (unsigned long)(~(1UL << (BITS_PER_LONG - 1))));
ret = bpf_jit_emit_func_call_rel(image, ro_image, ctx,
(unsigned long)__bpf_tramp_exit);
if (ret)
@@ -972,7 +984,6 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
struct bpf_tramp_links *tlinks, void *func_addr)
{
- struct bpf_tramp_image im;
void *image;
int ret;
@@ -988,7 +999,13 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
if (!image)
return -ENOMEM;
- ret = __arch_prepare_bpf_trampoline(&im, image, image + PAGE_SIZE, image,
+ /*
+ * Pass NULL as bpf_tramp_image pointer to differentiate the intent to get the
+ * buffer size for trampoline here. This differentiation helps in accounting for
+ * maximum possible instructions if the JIT code size is likely to vary during
+ * the actual JIT compile of the trampoline.
+ */
+ ret = __arch_prepare_bpf_trampoline(NULL, image, image + PAGE_SIZE, image,
m, flags, tlinks, func_addr);
bpf_jit_free_exec(image);
--
2.48.1
The source register is not used for SET* and reading it can result in
a UBSAN out-of-bounds array access error, specifically when the MOPS
exception is taken from a SET* sequence with XZR (reg 31) as the
source. Architecturally this is the only case where a src/dst/size
field in the ESR can be reported as 31.
Prior to 2de451a329cf662b the code in do_el0_mops() was benign as the
use of pt_regs_read_reg() prevented the out-of-bounds access.
Fixes: 2de451a329cf662b ("KVM: arm64: Add handler for MOPS exceptions")
Cc: Kristina Martsenko <kristina.martsenko(a)arm.com>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Mark Rutland <mark.rutland(a)arm.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: stable(a)vger.kernel.org
Reviewed-by: Marc Zyngier <maz(a)kernel.org>
Signed-off-by: Keir Fraser <keirf(a)google.com>
---
arch/arm64/include/asm/traps.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index d780d1bd2eac..82cf1f879c61 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -109,10 +109,9 @@ static inline void arm64_mops_reset_regs(struct user_pt_regs *regs, unsigned lon
int dstreg = ESR_ELx_MOPS_ISS_DESTREG(esr);
int srcreg = ESR_ELx_MOPS_ISS_SRCREG(esr);
int sizereg = ESR_ELx_MOPS_ISS_SIZEREG(esr);
- unsigned long dst, src, size;
+ unsigned long dst, size;
dst = regs->regs[dstreg];
- src = regs->regs[srcreg];
size = regs->regs[sizereg];
/*
@@ -129,6 +128,7 @@ static inline void arm64_mops_reset_regs(struct user_pt_regs *regs, unsigned lon
}
} else {
/* CPY* instruction */
+ unsigned long src = regs->regs[srcreg];
if (!(option_a ^ wrong_option)) {
/* Format is from Option B */
if (regs->pstate & PSR_N_BIT) {
--
2.49.0.395.g12beb8f557-goog
ARCH_DMA_MINALIGN is 1 by default, but some LoongArch-specific devices
(such as APBDMA) require 16 bytes alignment. When the data buffer length
is too small, the hardware may make an error writing cacheline. Thus, it
is dangerous to allocate a small memory buffer for DMA. It's always safe
to define ARCH_DMA_MINALIGN as L1_CACHE_BYTES but unnecessary (kmalloc()
need small memory objects). Therefore, just increase it to 16.
Cc: stable(a)vger.kernel.org
Tested-by: Binbin Zhou <zhoubinbin(a)loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai(a)loongson.cn>
---
arch/loongarch/include/asm/cache.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/loongarch/include/asm/cache.h b/arch/loongarch/include/asm/cache.h
index 1b6d09617199..aa622c754414 100644
--- a/arch/loongarch/include/asm/cache.h
+++ b/arch/loongarch/include/asm/cache.h
@@ -8,6 +8,8 @@
#define L1_CACHE_SHIFT CONFIG_L1_CACHE_SHIFT
#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)
+#define ARCH_DMA_MINALIGN (16)
+
#define __read_mostly __section(".data..read_mostly")
#endif /* _ASM_CACHE_H */
--
2.47.1
As part of I3C driver probing sequence for particular device instance,
While adding to queue it is trying to access ibi variable of dev which is
not yet initialized causing "Unable to handle kernel read from unreadable
memory" resulting in kernel panic.
Below is the sequence where this issue happened.
1. During boot up sequence IBI is received at host from the slave device
before requesting for IBI, Usually will request IBI by calling
i3c_device_request_ibi() during probe of slave driver.
2. Since master code trying to access IBI Variable for the particular
device instance before actually it initialized by slave driver,
due to this randomly accessing the address and causing kernel panic.
3. i3c_device_request_ibi() function invoked by the slave driver where
dev->ibi = ibi; assigned as part of function call
i3c_dev_request_ibi_locked().
4. But when IBI request sent by slave device, master code trying to access
this variable before its initialized due to this race condition
situation kernel panic happened.
Fixes: 3a379bbcea0af ("i3c: Add core I3C infrastructure")
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/lkml/Z9gjGYudiYyl3bSe@lizhi-Precision-Tower-5810/
Signed-off-by: Manjunatha Venkatesh <manjunatha.venkatesh(a)nxp.com>
---
Changes since v4:
- Fix added at generic places master.c which is applicable for all platforms
drivers/i3c/master.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index d5dc4180afbc..c65006aa0684 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -2561,6 +2561,9 @@ static void i3c_master_unregister_i3c_devs(struct i3c_master_controller *master)
*/
void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot)
{
+ if (!dev->ibi || !slot)
+ return;
+
atomic_inc(&dev->ibi->pending_ibis);
queue_work(dev->ibi->wq, &slot->work);
}
--
2.46.1
Commit under Fixes assigned the value of 'linkdown_irq_regfield' for the
J784S4 SoC as 'LINK_DOWN' which corresponds to BIT(1). However, according
to the Technical Reference Manual and Register Documentation for the J784S4
SoC [0], BIT(1) corresponds to "ENABLE_SYS_EN_PCIE_DPA_1" which is __NOT__
the field for the link-state interrupt. Instead, it is BIT(10) of the
"PCIE_INTD_ENABLE_REG_SYS_2" register that corresponds to the link-state
field named as "ENABLE_SYS_EN_PCIE_LINK_STATE".
Hence, set 'linkdown_irq_regfield' to the macro 'J7200_LINK_DOWN' which
expands to BIT(10) and was first defined for the J7200 SoC. Other SoCs
already reuse this macro since it accurately represents the link-state
field in their respective "PCIE_INTD_ENABLE_REG_SYS_2" register.
[0]: https://www.ti.com/lit/zip/spruj52
Fixes: e49ad667815d ("PCI: j721e: Add TI J784S4 PCIe configuration")
Cc: stable(a)vger.kernel.org
Signed-off-by: Siddharth Vadapalli <s-vadapalli(a)ti.com>
---
Hello,
This patch is based on commit
48a5eed9ad58 Merge tag 'devicetree-fixes-for-6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
of the master branch of Linux.
Patch has been tested on J784S4-EVM, validating that disconnecting an
Endpoint Device connected to J784S4-EVM results in the following message
on the J784S4-EVM:
j721e-pcie 2900000.pcie: LINK DOWN!
which wasn't seen earlier.
Regards,
Siddharth.
drivers/pci/controller/cadence/pci-j721e.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 0341d51d6aed..1da9d9918d0d 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -376,13 +376,13 @@ static const struct j721e_pcie_data j784s4_pcie_rc_data = {
.mode = PCI_MODE_RC,
.quirk_retrain_flag = true,
.byte_access_allowed = false,
- .linkdown_irq_regfield = LINK_DOWN,
+ .linkdown_irq_regfield = J7200_LINK_DOWN,
.max_lanes = 4,
};
static const struct j721e_pcie_data j784s4_pcie_ep_data = {
.mode = PCI_MODE_EP,
- .linkdown_irq_regfield = LINK_DOWN,
+ .linkdown_irq_regfield = J7200_LINK_DOWN,
.max_lanes = 4,
};
--
2.34.1
The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 800f1059c99e2b39899bdc67a7593a7bea6375d8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025032417-prior-uncooked-bf1f@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 800f1059c99e2b39899bdc67a7593a7bea6375d8 Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov(a)linux.intel.com>
Date: Mon, 10 Mar 2025 10:28:55 +0200
Subject: [PATCH] mm/page_alloc: fix memory accept before watermarks gets
initialized
Watermarks are initialized during the postcore initcall. Until then, all
watermarks are set to zero. This causes cond_accept_memory() to
incorrectly skip memory acceptance because a watermark of 0 is always met.
This can lead to a premature OOM on boot.
To ensure progress, accept one MAX_ORDER page if the watermark is zero.
Link: https://lkml.kernel.org/r/20250310082855.2587122-1-kirill.shutemov@linux.in…
Fixes: dcdfdd40fa82 ("mm: Add support for unaccepted memory")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Tested-by: Farrah Chen <farrah.chen(a)intel.com>
Reported-by: Farrah Chen <farrah.chen(a)intel.com>
Acked-by: Vlastimil Babka <vbabka(a)suse.cz>
Reviewed-by: Pankaj Gupta <pankaj.gupta(a)amd.com>
Cc: Ashish Kalra <ashish.kalra(a)amd.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe(a)intel.com>
Cc: Mel Gorman <mgorman(a)techsingularity.net>
Cc: "Mike Rapoport (IBM)" <rppt(a)kernel.org>
Cc: Thomas Lendacky <thomas.lendacky(a)amd.com>
Cc: <stable(a)vger.kernel.org> [6.5+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 94917c729120..542d25f77be8 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7004,7 +7004,7 @@ static inline bool has_unaccepted_memory(void)
static bool cond_accept_memory(struct zone *zone, unsigned int order)
{
- long to_accept;
+ long to_accept, wmark;
bool ret = false;
if (!has_unaccepted_memory())
@@ -7013,8 +7013,18 @@ static bool cond_accept_memory(struct zone *zone, unsigned int order)
if (list_empty(&zone->unaccepted_pages))
return false;
+ wmark = promo_wmark_pages(zone);
+
+ /*
+ * Watermarks have not been initialized yet.
+ *
+ * Accepting one MAX_ORDER page to ensure progress.
+ */
+ if (!wmark)
+ return try_to_accept_memory_one(zone);
+
/* How much to accept to get to promo watermark? */
- to_accept = promo_wmark_pages(zone) -
+ to_accept = wmark -
(zone_page_state(zone, NR_FREE_PAGES) -
__zone_watermark_unusable_free(zone, order, 0) -
zone_page_state(zone, NR_UNACCEPTED));