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* [PATCH 5/5] powerpc/xive: Map one IPI interrupt per node
From: Cédric Le Goater @ 2021-02-09 16:19 UTC (permalink / raw)
  To: linuxppc-dev; +Cc: Cédric Le Goater
In-Reply-To: <20210209161936.377760-1-clg@kaod.org>

ipistorm [*] can be used to benchmark the raw interrupt rate of an
interrupt controller by measuring the number of IPIs a system can
sustain. When applied to the XIVE interrupt controller of POWER9 and
POWER10 systems, a significant drop of the interrupt rate can be
observed when crossing the second node boundary.

This is due to the fact that a single IPI interrupt is used for all
CPUs of the system. The structure is shared and the cache line updates
impact greatly the traffic between nodes and the overall IPI
performance.

As a workaround, the impact can be reduced by deactivating the IRQ
lockup detector ("noirqdebug") which does a lot of accounting in the
Linux IRQ descriptor structure and is responsible for most of the
performance penalty.

As a fix, this proposal allocates an IPI interrupt per node, to be
shared by all CPUs of that node. It solves the scaling issue, the IRQ
lockup detector still has an impact but the XIVE interrupt rate scales
linearly. It also improves the "noirqdebug" case as showed in the
tables below.

 * P9 DD2.2 - 2s * 64 threads

                                               "noirqdebug"
                        Mint/s                    Mint/s
 chips  cpus      IPI/sys   IPI/chip       IPI/chip    IPI/sys
 --------------------------------------------------------------
 1      0-15     4.984023   4.875405       4.996536   5.048892
        0-31    10.879164  10.544040      10.757632  11.037859
        0-47    15.345301  14.688764      14.926520  15.310053
        0-63    17.064907  17.066812      17.613416  17.874511
 2      0-79    11.768764  21.650749      22.689120  22.566508
        0-95    10.616812  26.878789      28.434703  28.320324
        0-111   10.151693  31.397803      31.771773  32.388122
        0-127    9.948502  33.139336      34.875716  35.224548

 * P10 DD1 - 4s (not homogeneous) 352 threads

                                               "noirqdebug"
                        Mint/s                    Mint/s
 chips  cpus      IPI/sys   IPI/chip       IPI/chip    IPI/sys
 --------------------------------------------------------------
 1      0-15     2.409402   2.364108       2.383303   2.395091
        0-31     6.028325   6.046075       6.089999   6.073750
        0-47     8.655178   8.644531       8.712830   8.724702
        0-63    11.629652  11.735953      12.088203  12.055979
        0-79    14.392321  14.729959      14.986701  14.973073
        0-95    12.604158  13.004034      17.528748  17.568095
 2      0-111    9.767753  13.719831      19.968606  20.024218
        0-127    6.744566  16.418854      22.898066  22.995110
        0-143    6.005699  19.174421      25.425622  25.417541
        0-159    5.649719  21.938836      27.952662  28.059603
        0-175    5.441410  24.109484      31.133915  31.127996
 3      0-191    5.318341  24.405322      33.999221  33.775354
        0-207    5.191382  26.449769      36.050161  35.867307
        0-223    5.102790  29.356943      39.544135  39.508169
        0-239    5.035295  31.933051      42.135075  42.071975
        0-255    4.969209  34.477367      44.655395  44.757074
 4      0-271    4.907652  35.887016      47.080545  47.318537
        0-287    4.839581  38.076137      50.464307  50.636219
        0-303    4.786031  40.881319      53.478684  53.310759
        0-319    4.743750  43.448424      56.388102  55.973969
        0-335    4.709936  45.623532      59.400930  58.926857
        0-351    4.681413  45.646151      62.035804  61.830057

[*] https://github.com/antonblanchard/ipistorm

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 arch/powerpc/sysdev/xive/xive-internal.h |  2 --
 arch/powerpc/sysdev/xive/common.c        | 39 ++++++++++++++++++------
 2 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/arch/powerpc/sysdev/xive/xive-internal.h b/arch/powerpc/sysdev/xive/xive-internal.h
index 9cf57c722faa..b3a456fdd3a5 100644
--- a/arch/powerpc/sysdev/xive/xive-internal.h
+++ b/arch/powerpc/sysdev/xive/xive-internal.h
@@ -5,8 +5,6 @@
 #ifndef __XIVE_INTERNAL_H
 #define __XIVE_INTERNAL_H
 
-#define XIVE_IPI_HW_IRQ		0 /* interrupt source # for IPIs */
-
 /*
  * A "disabled" interrupt should never fire, to catch problems
  * we set its logical number to this
diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index 30034af4462b..a1e61a5cf927 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -65,8 +65,16 @@ static struct irq_domain *xive_irq_domain;
 #ifdef CONFIG_SMP
 static struct irq_domain *xive_ipi_irq_domain;
 
-/* The IPIs all use the same logical irq number */
-static u32 xive_ipi_irq;
+/* The IPIs use the same logical irq number when on the same chip */
+static struct xive_ipi_desc {
+	unsigned int irq;
+	char name[8]; /* enough bytes to fit IPI-XXX */
+} *xive_ipis;
+
+static unsigned int xive_ipi_cpu_to_irq(unsigned int cpu)
+{
+	return xive_ipis[cpu_to_node(cpu)].irq;
+}
 #endif
 
 /* Xive state for each CPU */
@@ -1087,25 +1095,36 @@ static const struct irq_domain_ops xive_ipi_irq_domain_ops = {
 
 static void __init xive_request_ipi(void)
 {
-	unsigned int virq;
+	unsigned int node;
 
-	xive_ipi_irq_domain = irq_domain_add_linear(NULL, 1,
+	xive_ipi_irq_domain = irq_domain_add_linear(NULL, nr_node_ids,
 						    &xive_ipi_irq_domain_ops, NULL);
 	if (WARN_ON(xive_ipi_irq_domain == NULL))
 		return;
 
-	/* Initialize it */
-	virq = irq_create_mapping(xive_ipi_irq_domain, XIVE_IPI_HW_IRQ);
-	xive_ipi_irq = virq;
+	xive_ipis = kcalloc(nr_node_ids, sizeof(*xive_ipis), GFP_KERNEL | __GFP_NOFAIL);
+	for_each_node(node) {
+		struct xive_ipi_desc *xid = &xive_ipis[node];
+		irq_hw_number_t node_ipi_hwirq = node;
+
+		/*
+		 * Map one IPI interrupt per node for all cpus of that node.
+		 * Since the HW interrupt number doesn't have any meaning,
+		 * simply use the node number.
+		 */
+		xid->irq = irq_create_mapping(xive_ipi_irq_domain, node_ipi_hwirq);
+		snprintf(xid->name, sizeof(xid->name), "IPI-%d", node);
 
-	WARN_ON(request_irq(virq, xive_muxed_ipi_action,
-			    IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
+		WARN_ON(request_irq(xid->irq, xive_muxed_ipi_action,
+				    IRQF_PERCPU | IRQF_NO_THREAD, xid->name, NULL));
+	}
 }
 
 static int xive_setup_cpu_ipi(unsigned int cpu)
 {
 	struct xive_cpu *xc;
 	int rc;
+	unsigned int xive_ipi_irq = xive_ipi_cpu_to_irq(cpu);
 
 	pr_debug("Setting up IPI for CPU %d\n", cpu);
 
@@ -1146,6 +1165,8 @@ static int xive_setup_cpu_ipi(unsigned int cpu)
 
 static void xive_cleanup_cpu_ipi(unsigned int cpu, struct xive_cpu *xc)
 {
+	unsigned int xive_ipi_irq = xive_ipi_cpu_to_irq(cpu);
+
 	/* Disable the IPI and free the IRQ data */
 
 	/* Already cleaned up ? */
-- 
2.26.2


^ permalink raw reply related

* [PATCH 1/5] powerpc/xive: Use cpu_to_node() instead of ibm, chip-id property
From: Cédric Le Goater @ 2021-02-09 16:19 UTC (permalink / raw)
  To: linuxppc-dev; +Cc: Cédric Le Goater
In-Reply-To: <20210209161936.377760-1-clg@kaod.org>

The 'chip_id' field of the XIVE CPU structure is used to choose a
target for a source located on the same chip when possible. This field
is assigned on the PowerNV platform using the "ibm,chip-id" property
on pSeries under KVM when NUMA nodes are defined but it is undefined
under PowerVM. The XIVE source structure has a similar field
'src_chip' which is only assigned on the PowerNV platform.

cpu_to_node() returns a compatible value on all platforms, 0 being the
default node. It will also give us the opportunity to set the affinity
of a source on pSeries when we can localize them.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 arch/powerpc/sysdev/xive/common.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index 7e08be5e5e4a..776871274b69 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -1336,16 +1336,11 @@ static int xive_prepare_cpu(unsigned int cpu)
 
 	xc = per_cpu(xive_cpu, cpu);
 	if (!xc) {
-		struct device_node *np;
-
 		xc = kzalloc_node(sizeof(struct xive_cpu),
 				  GFP_KERNEL, cpu_to_node(cpu));
 		if (!xc)
 			return -ENOMEM;
-		np = of_get_cpu_node(cpu, NULL);
-		if (np)
-			xc->chip_id = of_get_ibm_chip_id(np);
-		of_node_put(np);
+		xc->chip_id = cpu_to_node(cpu);
 		xc->hw_ipi = XIVE_BAD_IRQ;
 
 		per_cpu(xive_cpu, cpu) = xc;
-- 
2.26.2


^ permalink raw reply related

* [PATCH 4/5] powerpc/xive: Simplify xive_core_debug_show()
From: Cédric Le Goater @ 2021-02-09 16:19 UTC (permalink / raw)
  To: linuxppc-dev; +Cc: Cédric Le Goater
In-Reply-To: <20210209161936.377760-1-clg@kaod.org>

Now that the IPI interrupt has its own domain, the checks on the HW
interrupt number XIVE_IPI_HW_IRQ and on the chip can be replaced by a
check on the domain.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 arch/powerpc/sysdev/xive/common.c | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index 21e8f7ef5cc4..30034af4462b 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -1580,17 +1580,14 @@ static void xive_debug_show_cpu(struct seq_file *m, int cpu)
 	seq_puts(m, "\n");
 }
 
-static void xive_debug_show_irq(struct seq_file *m, u32 hw_irq, struct irq_data *d)
+static void xive_debug_show_irq(struct seq_file *m, struct irq_data *d)
 {
-	struct irq_chip *chip = irq_data_get_irq_chip(d);
+	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 	int rc;
 	u32 target;
 	u8 prio;
 	u32 lirq;
 
-	if (!is_xive_irq(chip))
-		return;
-
 	rc = xive_ops->get_irq_config(hw_irq, &target, &prio, &lirq);
 	if (rc) {
 		seq_printf(m, "IRQ 0x%08x : no config rc=%d\n", hw_irq, rc);
@@ -1628,16 +1625,9 @@ static int xive_core_debug_show(struct seq_file *m, void *private)
 
 	for_each_irq_desc(i, desc) {
 		struct irq_data *d = irq_desc_get_irq_data(desc);
-		unsigned int hw_irq;
-
-		if (!d)
-			continue;
-
-		hw_irq = (unsigned int)irqd_to_hwirq(d);
 
-		/* IPIs are special (HW number 0) */
-		if (hw_irq != XIVE_IPI_HW_IRQ)
-			xive_debug_show_irq(m, hw_irq, d);
+		if (d->domain == xive_irq_domain)
+			xive_debug_show_irq(m, d);
 	}
 	return 0;
 }
-- 
2.26.2


^ permalink raw reply related

* [PATCH 3/5] powerpc/xive: Remove useless check on XIVE_IPI_HW_IRQ
From: Cédric Le Goater @ 2021-02-09 16:19 UTC (permalink / raw)
  To: linuxppc-dev; +Cc: Cédric Le Goater
In-Reply-To: <20210209161936.377760-1-clg@kaod.org>

The IPI interrupt has its own domain now. Testing the HW interrupt
number is not needed anymore.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 arch/powerpc/sysdev/xive/common.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index 4aceac0f3046..21e8f7ef5cc4 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -1397,13 +1397,12 @@ static void xive_flush_cpu_queue(unsigned int cpu, struct xive_cpu *xc)
 		struct irq_desc *desc = irq_to_desc(irq);
 		struct irq_data *d = irq_desc_get_irq_data(desc);
 		struct xive_irq_data *xd;
-		unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 
 		/*
 		 * Ignore anything that isn't a XIVE irq and ignore
 		 * IPIs, so can just be dropped.
 		 */
-		if (d->domain != xive_irq_domain || hw_irq == XIVE_IPI_HW_IRQ)
+		if (d->domain != xive_irq_domain)
 			continue;
 
 		/*
-- 
2.26.2


^ permalink raw reply related

* Re: [PATCH v5 20/22] powerpc/syscall: Avoid storing 'current' in another pointer
From: Christophe Leroy @ 2021-02-09 17:03 UTC (permalink / raw)
  To: David Laight, 'Segher Boessenkool', Nicholas Piggin
  Cc: Paul Mackerras, msuchanek@suse.de, linuxppc-dev@lists.ozlabs.org,
	linux-kernel@vger.kernel.org
In-Reply-To: <d35cc46eca474b2c9f94a4de269321e7@AcuMS.aculab.com>



Le 09/02/2021 à 15:31, David Laight a écrit :
> From: Segher Boessenkool
>> Sent: 09 February 2021 13:51
>>
>> On Tue, Feb 09, 2021 at 12:36:20PM +1000, Nicholas Piggin wrote:
>>> What if you did this?
>>
>>> +static inline struct task_struct *get_current(void)
>>> +{
>>> +	register struct task_struct *task asm ("r2");
>>> +
>>> +	return task;
>>> +}
>>
>> Local register asm variables are *only* guaranteed to live in that
>> register as operands to an asm.  See
>>    https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html#Local-Register-Variables
>> ("The only supported use" etc.)
>>
>> You can do something like
>>
>> static inline struct task_struct *get_current(void)
>> {
>> 	register struct task_struct *task asm ("r2");
>>
>> 	asm("" : "+r"(task));
>>
>> 	return task;
>> }
>>
>> which makes sure that "task" actually is in r2 at the point of that asm.
> 
> If "r2" always contains current (and is never assigned by the compiler)
> why not use a global register variable for it?
> 


The change proposed by Nick doesn't solve the issue.

The problem is that at the begining of the function we have:

	unsigned long *ti_flagsp = &current_thread_info()->flags;

When the function uses ti_flagsp for the first time, it does use 112(r2)

Then the function calls some other functions.

Most likely because the function could update 'current', GCC copies r2 into r30, so that if r2 get 
changed by the called function, ti_flagsp is still based on the previous value of current.

Allthough we know r2 wont change, GCC doesn't know it. And in order to save r2 into r30, it needs to 
save r30 in the stack.


By using &current_thread_info()->flags directly instead of this intermediaite ti_flagsp pointer, GCC 
uses r2 instead instead of doing a copy.


Nick, I don't understand the reason why you need that 'ti_flagsp' local var.

Christophe

^ permalink raw reply

* RE: [PATCH v5 20/22] powerpc/syscall: Avoid storing 'current' in another pointer
From: David Laight @ 2021-02-09 17:16 UTC (permalink / raw)
  To: 'Christophe Leroy', 'Segher Boessenkool',
	Nicholas Piggin
  Cc: Paul Mackerras, msuchanek@suse.de, linuxppc-dev@lists.ozlabs.org,
	linux-kernel@vger.kernel.org
In-Reply-To: <f6ae2e77-3a89-c294-9a6e-58d84fbb46b1@csgroup.eu>

From: Christophe Leroy <christophe.leroy@csgroup.eu>
> Sent: 09 February 2021 17:04
> 
> Le 09/02/2021 à 15:31, David Laight a écrit :
> > From: Segher Boessenkool
> >> Sent: 09 February 2021 13:51
> >>
> >> On Tue, Feb 09, 2021 at 12:36:20PM +1000, Nicholas Piggin wrote:
> >>> What if you did this?
> >>
> >>> +static inline struct task_struct *get_current(void)
> >>> +{
> >>> +	register struct task_struct *task asm ("r2");
> >>> +
> >>> +	return task;
> >>> +}
> >>
> >> Local register asm variables are *only* guaranteed to live in that
> >> register as operands to an asm.  See
> >>    https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html#Local-Register-Variables
> >> ("The only supported use" etc.)
> >>
> >> You can do something like
> >>
> >> static inline struct task_struct *get_current(void)
> >> {
> >> 	register struct task_struct *task asm ("r2");
> >>
> >> 	asm("" : "+r"(task));
> >>
> >> 	return task;
> >> }
> >>
> >> which makes sure that "task" actually is in r2 at the point of that asm.
> >
> > If "r2" always contains current (and is never assigned by the compiler)
> > why not use a global register variable for it?
> >
> 
> 
> The change proposed by Nick doesn't solve the issue.
> 
> The problem is that at the begining of the function we have:
> 
> 	unsigned long *ti_flagsp = &current_thread_info()->flags;
> 
> When the function uses ti_flagsp for the first time, it does use 112(r2)
> 
> Then the function calls some other functions.
> 
> Most likely because the function could update 'current', GCC copies r2 into r30, so that if r2 get
> changed by the called function, ti_flagsp is still based on the previous value of current.
> 
> Allthough we know r2 wont change, GCC doesn't know it. And in order to save r2 into r30, it needs to
> save r30 in the stack.
> 
> 
> By using &current_thread_info()->flags directly instead of this intermediaite ti_flagsp pointer, GCC
> uses r2 instead instead of doing a copy.

Does marking current_thread_info() 'pure' (I think that the right one)
work - so that gcc knows its result doesn't depend on external data
and that it doesn't change external data.

Although I'm not 100% how well those attributes actually work.

> Nick, I don't understand the reason why you need that 'ti_flagsp' local var.

Probably to save typing.

I sometimes reload locals after function calls.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)

^ permalink raw reply

* [PATCH v17 00/10] Carry forward IMA measurement log on kexec on ARM64
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev

On kexec file load Integrity Measurement Architecture (IMA) subsystem
may verify the IMA signature of the kernel and initramfs, and measure
it.  The command line parameters passed to the kernel in the kexec call
may also be measured by IMA.  A remote attestation service can verify
a TPM quote based on the TPM event log, the IMA measurement list, and
the TPM PCR data.  This can be achieved only if the IMA measurement log
is carried over from the current kernel to the next kernel across
the kexec call.

powerpc already supports carrying forward the IMA measurement log on
kexec.  This patch set adds support for carrying forward the IMA
measurement log on kexec on ARM64.

This patch set moves the platform independent code defined for powerpc
such that it can be reused for other platforms as well.  A chosen node
"linux,ima-kexec-buffer" is added to the DTB for ARM64 to hold
the address and the size of the memory reserved to carry
the IMA measurement log.

This patch set has been tested for ARM64 platform using QEMU.
I would like help from the community for testing this change on powerpc.
Thanks.

This patch set is based on
commit 96acc833dec8 ("ima: Free IMA measurement buffer after kexec syscall")
in https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git
"next-integrity" branch.

Changelog:

v17
  - Renamed of_kexec_setup_new_fdt() to of_kexec_alloc_and_setup_fdt(),
    and moved memory allocation for the new FDT to this function.

v16
  - Defined functions to allocate and free buffer for FDT for powerpc
    and arm64.
  - Moved ima_buffer_addr and ima_buffer_size fields from
    "struct kimage_arch" in powerpc to "struct kimage"
v15
  - Included Rob's patches in the patch set, and rebased
    the changes to "next-integrity" branch.
  - Allocate memory for DTB, on arm64, using kmalloc() instead of
    vmalloc() to keep it consistent with powerpc implementation.
  - Call of_kexec_setup_new_fdt() from setup_new_fdt_ppc64() and
    remove setup_new_fdt() in the same patch to keep it bisect safe.

v14
  - Select CONFIG_HAVE_IMA_KEXEC for CONFIG_KEXEC_FILE, for powerpc
    and arm64, if CONFIG_IMA is enabled.
  - Use IS_ENABLED() macro instead of "#ifdef" in remove_ima_buffer(),
    ima_get_kexec_buffer(), and ima_free_kexec_buffer().
  - Call of_kexec_setup_new_fdt() from setup_new_fdt_ppc64() and
    remove setup_new_fdt() in "arch/powerpc/kexec/file_load.c".

v13
  - Moved the arch independent functions to drivers/of/kexec.c
    and then refactored the code.
  - Moved arch_ima_add_kexec_buffer() to
    security/integrity/ima/ima_kexec.c

v12
  - Use fdt_appendprop_addrrange() in setup_ima_buffer()
    to setup the IMA measurement list property in
    the device tree.
  - Moved architecture independent functions from
    "arch/powerpc/kexec/ima.c" to "drivers/of/kexec."
  - Deleted "arch/powerpc/kexec/ima.c" and
    "arch/powerpc/include/asm/ima.h".

v11
  - Rebased the changes on the kexec code refactoring done by
    Rob Herring in his "dt/kexec" branch
  - Removed "extern" keyword in function declarations
  - Removed unnecessary header files included in C files
  - Updated patch descriptions per Thiago's comments

v10
  - Moved delete_fdt_mem_rsv(), remove_ima_buffer(),
    get_ima_kexec_buffer, and get_root_addr_size_cells()
    to drivers/of/kexec.c
  - Moved arch_ima_add_kexec_buffer() to
    security/integrity/ima/ima_kexec.c
  - Conditionally define IMA buffer fields in struct kimage_arch

v9
  - Moved delete_fdt_mem_rsv() to drivers/of/kexec_fdt.c
  - Defined a new function get_ima_kexec_buffer() in
    drivers/of/ima_kexec.c to replace do_get_kexec_buffer()
  - Changed remove_ima_kexec_buffer() to the original function name
    remove_ima_buffer()
  - Moved remove_ima_buffer() to drivers/of/ima_kexec.c
  - Moved ima_get_kexec_buffer() and ima_free_kexec_buffer()
    to security/integrity/ima/ima_kexec.c

v8:
  - Moved remove_ima_kexec_buffer(), do_get_kexec_buffer(), and
    delete_fdt_mem_rsv() to drivers/of/fdt.c
  - Moved ima_dump_measurement_list() and ima_add_kexec_buffer()
    back to security/integrity/ima/ima_kexec.c

v7:
  - Renamed remove_ima_buffer() to remove_ima_kexec_buffer() and moved
    this function definition to kernel.
  - Moved delete_fdt_mem_rsv() definition to kernel
  - Moved ima_dump_measurement_list() and ima_add_kexec_buffer() to
    a new file namely ima_kexec_fdt.c in IMA

v6:
  - Remove any existing FDT_PROP_IMA_KEXEC_BUFFER property in the device
    tree and also its corresponding memory reservation in the currently
    running kernel.
  - Moved the function remove_ima_buffer() defined for powerpc to IMA
    and renamed the function to ima_remove_kexec_buffer(). Also, moved
    delete_fdt_mem_rsv() from powerpc to IMA.

v5:
  - Merged get_addr_size_cells() and do_get_kexec_buffer() into a single
    function when moving the arch independent code from powerpc to IMA
  - Reverted the change to use FDT functions in powerpc code and added
    back the original code in get_addr_size_cells() and
    do_get_kexec_buffer() for powerpc.
  - Added fdt_add_mem_rsv() for ARM64 to reserve the memory for
    the IMA log buffer during kexec.
  - Fixed the warning reported by kernel test bot for ARM64
    arch_ima_add_kexec_buffer() - moved this function to a new file
    namely arch/arm64/kernel/ima_kexec.c

v4:
  - Submitting the patch series on behalf of the original author
    Prakhar Srivastava <prsriva@linux.microsoft.com>
  - Moved FDT_PROP_IMA_KEXEC_BUFFER ("linux,ima-kexec-buffer") to
    libfdt.h so that it can be shared by multiple platforms.

v3:
Breakup patches further into separate patches.
  - Refactoring non architecture specific code out of powerpc
  - Update powerpc related code to use fdt functions
  - Update IMA buffer read related code to use of functions
  - Add support to store the memory information of the IMA
    measurement logs to be carried forward.
  - Update the property strings to align with documented nodes
    https://github.com/devicetree-org/dt-schema/pull/46

v2:
  Break patches into separate patches.
  - Powerpc related Refactoring
  - Updating the docuemntation for chosen node
  - Updating arm64 to support IMA buffer pass

v1:
  Refactoring carrying over IMA measuremnet logs over Kexec. This patch
    moves the non-architecture specific code out of powerpc and adds to
    security/ima.(Suggested by Thiago)
  Add Documentation regarding the ima-kexec-buffer node in the chosen
    node documentation

v0:
  Add a layer of abstraction to use the memory reserved by device tree
    for ima buffer pass.
  Add support for ima buffer pass using reserved memory for arm64 kexec.
    Update the arch sepcific code path in kexec file load to store the
    ima buffer in the reserved memory. The same reserved memory is read
    on kexec or cold boot.

Lakshmi Ramasubramanian (6):
  powerpc: Move ima buffer fields to struct kimage
  powerpc: Enable passing IMA log to next kernel on kexec
  powerpc: Move arch independent ima kexec functions to
    drivers/of/kexec.c
  kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT
  powerpc: Delete unused function delete_fdt_mem_rsv()
  arm64: Enable passing IMA log to next kernel on kexec

Rob Herring (4):
  powerpc: Rename kexec elfcorehdr_addr to elf_headers_mem
  of: Add a common kexec FDT setup function
  arm64: Use common of_kexec_alloc_and_setup_fdt()
  powerpc: Use common of_kexec_alloc_and_setup_fdt()

 arch/arm64/Kconfig                     |   1 +
 arch/arm64/kernel/machine_kexec_file.c | 180 +---------
 arch/powerpc/Kconfig                   |   2 +-
 arch/powerpc/include/asm/ima.h         |  30 --
 arch/powerpc/include/asm/kexec.h       |  12 +-
 arch/powerpc/kexec/Makefile            |   7 -
 arch/powerpc/kexec/elf_64.c            |  29 +-
 arch/powerpc/kexec/file_load.c         | 183 +---------
 arch/powerpc/kexec/file_load_64.c      |  11 +-
 arch/powerpc/kexec/ima.c               | 219 ------------
 drivers/of/Makefile                    |   6 +
 drivers/of/kexec.c                     | 473 +++++++++++++++++++++++++
 include/linux/kexec.h                  |   3 +
 include/linux/of.h                     |  20 ++
 security/integrity/ima/ima.h           |   4 -
 security/integrity/ima/ima_kexec.c     |   3 +-
 16 files changed, 539 insertions(+), 644 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/ima.h
 delete mode 100644 arch/powerpc/kexec/ima.c
 create mode 100644 drivers/of/kexec.c

-- 
2.30.0


^ permalink raw reply

* [PATCH v17 02/10] of: Add a common kexec FDT setup function
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

From: Rob Herring <robh@kernel.org>

Both arm64 and powerpc do essentially the same FDT /chosen setup for
kexec.  The differences are either omissions that arm64 should have
or additional properties that will be ignored.  The setup code can be
combined and shared by both powerpc and arm64.

The differences relative to the arm64 version:
 - If /chosen doesn't exist, it will be created (should never happen).
 - Any old dtb and initrd reserved memory will be released.
 - The new initrd and elfcorehdr are marked reserved.
 - "linux,booted-from-kexec" is set.

The differences relative to the powerpc version:
 - "kaslr-seed" and "rng-seed" may be set.
 - "linux,elfcorehdr" is set.
 - Any existing "linux,usable-memory-range" is removed.

Combine the code for setting up the /chosen node in the FDT and updating
the memory reservation for kexec, for powerpc and arm64, in
of_kexec_alloc_and_setup_fdt() and move it to "drivers/of/kexec.c".

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 drivers/of/Makefile |   6 ++
 drivers/of/kexec.c  | 258 ++++++++++++++++++++++++++++++++++++++++++++
 include/linux/of.h  |  13 +++
 3 files changed, 277 insertions(+)
 create mode 100644 drivers/of/kexec.c

diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index 6e1e5212f058..c13b982084a3 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -14,4 +14,10 @@ obj-$(CONFIG_OF_RESOLVE)  += resolver.o
 obj-$(CONFIG_OF_OVERLAY) += overlay.o
 obj-$(CONFIG_OF_NUMA) += of_numa.o
 
+ifdef CONFIG_KEXEC_FILE
+ifdef CONFIG_OF_FLATTREE
+obj-y	+= kexec.o
+endif
+endif
+
 obj-$(CONFIG_OF_UNITTEST) += unittest-data/
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
new file mode 100644
index 000000000000..469e09613cdd
--- /dev/null
+++ b/drivers/of/kexec.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Arm Limited
+ *
+ * Based on arch/arm64/kernel/machine_kexec_file.c:
+ *  Copyright (C) 2018 Linaro Limited
+ *
+ * And arch/powerpc/kexec/file_load.c:
+ *  Copyright (C) 2016  IBM Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/random.h>
+#include <linux/types.h>
+
+/* relevant device tree properties */
+#define FDT_PROP_KEXEC_ELFHDR	"linux,elfcorehdr"
+#define FDT_PROP_MEM_RANGE	"linux,usable-memory-range"
+#define FDT_PROP_INITRD_START	"linux,initrd-start"
+#define FDT_PROP_INITRD_END	"linux,initrd-end"
+#define FDT_PROP_BOOTARGS	"bootargs"
+#define FDT_PROP_KASLR_SEED	"kaslr-seed"
+#define FDT_PROP_RNG_SEED	"rng-seed"
+#define RNG_SEED_SIZE		128
+
+/**
+ * fdt_find_and_del_mem_rsv - delete memory reservation with given address and size
+ *
+ * @fdt:	Flattened device tree for the current kernel.
+ * @start:	Starting address of the reserved memory.
+ * @size:	Size of the reserved memory.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned long size)
+{
+	int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
+
+	for (i = 0; i < num_rsvs; i++) {
+		u64 rsv_start, rsv_size;
+
+		ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
+		if (ret) {
+			pr_err("Malformed device tree.\n");
+			return -EINVAL;
+		}
+
+		if (rsv_start == start && rsv_size == size) {
+			ret = fdt_del_mem_rsv(fdt, i);
+			if (ret) {
+				pr_err("Error deleting device tree reservation.\n");
+				return -EINVAL;
+			}
+
+			return 0;
+		}
+	}
+
+	return -ENOENT;
+}
+
+/*
+ * of_kexec_alloc_and_setup_fdt - Alloc and setup a new Flattened Device Tree
+ *
+ * @image:		kexec image being loaded.
+ * @initrd_load_addr:	Address where the next initrd will be loaded.
+ * @initrd_len:		Size of the next initrd, or 0 if there will be none.
+ * @cmdline:		Command line for the next kernel, or NULL if there will
+ *			be none.
+ *
+ * Return: fdt on success, or NULL errno on error.
+ */
+void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
+				   unsigned long initrd_load_addr,
+				   unsigned long initrd_len,
+				   const char *cmdline)
+{
+	void *fdt;
+	int ret, chosen_node;
+	const void *prop;
+	unsigned long fdt_size;
+
+	fdt_size = fdt_totalsize(initial_boot_params) +
+		   (cmdline ? strlen(cmdline) : 0) +
+		   FDT_EXTRA_SPACE;
+
+	fdt = kvmalloc(fdt_size, GFP_KERNEL);
+	if (!fdt)
+		return NULL;
+
+	ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
+	if (ret < 0) {
+		pr_err("Error %d setting up the new device tree.\n", ret);
+		goto out;
+	}
+
+	/* Remove memory reservation for the current device tree. */
+	ret = fdt_find_and_del_mem_rsv(fdt, __pa(initial_boot_params),
+				       fdt_totalsize(initial_boot_params));
+	if (ret == -EINVAL) {
+		pr_err("Error removing memory reservation.\n");
+		goto out;
+	}
+
+	chosen_node = fdt_path_offset(fdt, "/chosen");
+	if (chosen_node == -FDT_ERR_NOTFOUND)
+		chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
+					      "chosen");
+	if (chosen_node < 0) {
+		ret = chosen_node;
+		goto out;
+	}
+
+	ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KEXEC_ELFHDR);
+	if (ret && ret != -FDT_ERR_NOTFOUND)
+		goto out;
+	ret = fdt_delprop(fdt, chosen_node, FDT_PROP_MEM_RANGE);
+	if (ret && ret != -FDT_ERR_NOTFOUND)
+		goto out;
+
+	/* Did we boot using an initrd? */
+	prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
+	if (prop) {
+		u64 tmp_start, tmp_end, tmp_size;
+
+		tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+		prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
+		if (!prop) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+		/*
+		 * kexec reserves exact initrd size, while firmware may
+		 * reserve a multiple of PAGE_SIZE, so check for both.
+		 */
+		tmp_size = tmp_end - tmp_start;
+		ret = fdt_find_and_del_mem_rsv(fdt, tmp_start, tmp_size);
+		if (ret == -ENOENT)
+			ret = fdt_find_and_del_mem_rsv(fdt, tmp_start,
+						       round_up(tmp_size, PAGE_SIZE));
+		if (ret == -EINVAL)
+			goto out;
+	}
+
+	/* add initrd-* */
+	if (initrd_load_addr) {
+		ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_START,
+				      initrd_load_addr);
+		if (ret)
+			goto out;
+
+		ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_END,
+				      initrd_load_addr + initrd_len);
+		if (ret)
+			goto out;
+
+		ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
+		if (ret)
+			goto out;
+
+	} else {
+		ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_START);
+		if (ret && (ret != -FDT_ERR_NOTFOUND))
+			goto out;
+
+		ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_END);
+		if (ret && (ret != -FDT_ERR_NOTFOUND))
+			goto out;
+	}
+
+	if (image->type == KEXEC_TYPE_CRASH) {
+		/* add linux,elfcorehdr */
+		ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				FDT_PROP_KEXEC_ELFHDR,
+				image->arch.elf_headers_mem,
+				image->arch.elf_headers_sz);
+		if (ret)
+			goto out;
+
+		/*
+		 * Avoid elfcorehdr from being stomped on in kdump kernel by
+		 * setting up memory reserve map.
+		 */
+		ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
+				      image->arch.elf_headers_sz);
+		if (ret)
+			goto out;
+
+		/* add linux,usable-memory-range */
+		ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				FDT_PROP_MEM_RANGE,
+				crashk_res.start,
+				crashk_res.end - crashk_res.start + 1);
+		if (ret)
+			goto out;
+	}
+
+	/* add bootargs */
+	if (cmdline) {
+		ret = fdt_setprop_string(fdt, chosen_node, FDT_PROP_BOOTARGS, cmdline);
+		if (ret)
+			goto out;
+	} else {
+		ret = fdt_delprop(fdt, chosen_node, FDT_PROP_BOOTARGS);
+		if (ret && (ret != -FDT_ERR_NOTFOUND))
+			goto out;
+	}
+
+	/* add kaslr-seed */
+	ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KASLR_SEED);
+	if (ret == -FDT_ERR_NOTFOUND)
+		ret = 0;
+	else if (ret)
+		goto out;
+
+	if (rng_is_initialized()) {
+		u64 seed = get_random_u64();
+
+		ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_KASLR_SEED, seed);
+		if (ret)
+			goto out;
+	} else {
+		pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+				FDT_PROP_KASLR_SEED);
+	}
+
+	/* add rng-seed */
+	if (rng_is_initialized()) {
+		void *rng_seed;
+
+		ret = fdt_setprop_placeholder(fdt, chosen_node, FDT_PROP_RNG_SEED,
+				RNG_SEED_SIZE, &rng_seed);
+		if (ret)
+			goto out;
+		get_random_bytes(rng_seed, RNG_SEED_SIZE);
+	} else {
+		pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+				FDT_PROP_RNG_SEED);
+	}
+
+	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+
+out:
+	if (ret) {
+		kvfree(fdt);
+		fdt = NULL;
+	}
+
+	return fdt;
+}
diff --git a/include/linux/of.h b/include/linux/of.h
index 4b27c9a27df3..f0eff5e84353 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -560,6 +560,19 @@ int of_map_id(struct device_node *np, u32 id,
 
 phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
 
+/*
+ * Additional space needed for the buffer to build the new FDT
+ * so that we can add initrd, bootargs, kaslr-seed, rng-seed,
+ * userable-memory-range and elfcorehdr.
+ */
+#define FDT_EXTRA_SPACE 0x1000
+
+struct kimage;
+void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
+				   unsigned long initrd_load_addr,
+				   unsigned long initrd_len,
+				   const char *cmdline);
+
 #else /* CONFIG_OF */
 
 static inline void of_core_init(void)
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 01/10] powerpc: Rename kexec elfcorehdr_addr to elf_headers_mem
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

From: Rob Herring <robh@kernel.org>

The architecture specific field, elfcorehdr_addr in struct kimage_arch,
that holds the address of the buffer in memory for ELF core header for
powerpc has a different name than the one used for arm64.  This makes
it hard to have a common code for setting up the device tree for
kexec system call.

Rename elfcorehdr_addr to elf_headers_mem to align with arm64 name so
common code can use it.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 arch/powerpc/include/asm/kexec.h  | 2 +-
 arch/powerpc/kexec/file_load.c    | 4 ++--
 arch/powerpc/kexec/file_load_64.c | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 55d6ede30c19..dbf09d2f36d0 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -108,7 +108,7 @@ struct kimage_arch {
 	unsigned long backup_start;
 	void *backup_buf;
 
-	unsigned long elfcorehdr_addr;
+	unsigned long elf_headers_mem;
 	unsigned long elf_headers_sz;
 	void *elf_headers;
 
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 9a232bc36c8f..e452b11df631 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -45,7 +45,7 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
 		return NULL;
 
 	elfcorehdr_strlen = sprintf(cmdline_ptr, "elfcorehdr=0x%lx ",
-				    image->arch.elfcorehdr_addr);
+				    image->arch.elf_headers_mem);
 
 	if (elfcorehdr_strlen + cmdline_len > COMMAND_LINE_SIZE) {
 		pr_err("Appending elfcorehdr=<addr> exceeds cmdline size\n");
@@ -263,7 +263,7 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
 		 * Avoid elfcorehdr from being stomped on in kdump kernel by
 		 * setting up memory reserve map.
 		 */
-		ret = fdt_add_mem_rsv(fdt, image->arch.elfcorehdr_addr,
+		ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
 				      image->arch.elf_headers_sz);
 		if (ret) {
 			pr_err("Error reserving elfcorehdr memory: %s\n",
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index c69bcf9b547a..a05c19b3cc60 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -815,7 +815,7 @@ static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
 		goto out;
 	}
 
-	image->arch.elfcorehdr_addr = kbuf->mem;
+	image->arch.elf_headers_mem = kbuf->mem;
 	image->arch.elf_headers_sz = headers_sz;
 	image->arch.elf_headers = headers;
 out:
@@ -851,7 +851,7 @@ int load_crashdump_segments_ppc64(struct kimage *image,
 		return ret;
 	}
 	pr_debug("Loaded elf core header at 0x%lx, bufsz=0x%lx memsz=0x%lx\n",
-		 image->arch.elfcorehdr_addr, kbuf->bufsz, kbuf->memsz);
+		 image->arch.elf_headers_mem, kbuf->bufsz, kbuf->memsz);
 
 	return 0;
 }
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 03/10] arm64: Use common of_kexec_alloc_and_setup_fdt()
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

From: Rob Herring <robh@kernel.org>

The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".

Use the common of_kexec_alloc_and_setup_fdt() to setup the device tree
and update the memory reservation for kexec for arm64.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 arch/arm64/kernel/machine_kexec_file.c | 180 ++-----------------------
 1 file changed, 8 insertions(+), 172 deletions(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 03210f644790..5a203f4f31fd 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -15,23 +15,12 @@
 #include <linux/kexec.h>
 #include <linux/libfdt.h>
 #include <linux/memblock.h>
+#include <linux/of.h>
 #include <linux/of_fdt.h>
-#include <linux/random.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/vmalloc.h>
-#include <asm/byteorder.h>
-
-/* relevant device tree properties */
-#define FDT_PROP_KEXEC_ELFHDR	"linux,elfcorehdr"
-#define FDT_PROP_MEM_RANGE	"linux,usable-memory-range"
-#define FDT_PROP_INITRD_START	"linux,initrd-start"
-#define FDT_PROP_INITRD_END	"linux,initrd-end"
-#define FDT_PROP_BOOTARGS	"bootargs"
-#define FDT_PROP_KASLR_SEED	"kaslr-seed"
-#define FDT_PROP_RNG_SEED	"rng-seed"
-#define RNG_SEED_SIZE		128
 
 const struct kexec_file_ops * const kexec_file_loaders[] = {
 	&kexec_image_ops,
@@ -40,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
 
 int arch_kimage_file_post_load_cleanup(struct kimage *image)
 {
-	vfree(image->arch.dtb);
+	kvfree(image->arch.dtb);
 	image->arch.dtb = NULL;
 
 	vfree(image->arch.elf_headers);
@@ -50,162 +39,6 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
 	return kexec_image_post_load_cleanup_default(image);
 }
 
-static int setup_dtb(struct kimage *image,
-		     unsigned long initrd_load_addr, unsigned long initrd_len,
-		     char *cmdline, void *dtb)
-{
-	int off, ret;
-
-	ret = fdt_path_offset(dtb, "/chosen");
-	if (ret < 0)
-		goto out;
-
-	off = ret;
-
-	ret = fdt_delprop(dtb, off, FDT_PROP_KEXEC_ELFHDR);
-	if (ret && ret != -FDT_ERR_NOTFOUND)
-		goto out;
-	ret = fdt_delprop(dtb, off, FDT_PROP_MEM_RANGE);
-	if (ret && ret != -FDT_ERR_NOTFOUND)
-		goto out;
-
-	if (image->type == KEXEC_TYPE_CRASH) {
-		/* add linux,elfcorehdr */
-		ret = fdt_appendprop_addrrange(dtb, 0, off,
-				FDT_PROP_KEXEC_ELFHDR,
-				image->arch.elf_headers_mem,
-				image->arch.elf_headers_sz);
-		if (ret)
-			return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
-
-		/* add linux,usable-memory-range */
-		ret = fdt_appendprop_addrrange(dtb, 0, off,
-				FDT_PROP_MEM_RANGE,
-				crashk_res.start,
-				crashk_res.end - crashk_res.start + 1);
-		if (ret)
-			return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
-	}
-
-	/* add bootargs */
-	if (cmdline) {
-		ret = fdt_setprop_string(dtb, off, FDT_PROP_BOOTARGS, cmdline);
-		if (ret)
-			goto out;
-	} else {
-		ret = fdt_delprop(dtb, off, FDT_PROP_BOOTARGS);
-		if (ret && (ret != -FDT_ERR_NOTFOUND))
-			goto out;
-	}
-
-	/* add initrd-* */
-	if (initrd_load_addr) {
-		ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_START,
-				      initrd_load_addr);
-		if (ret)
-			goto out;
-
-		ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_END,
-				      initrd_load_addr + initrd_len);
-		if (ret)
-			goto out;
-	} else {
-		ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_START);
-		if (ret && (ret != -FDT_ERR_NOTFOUND))
-			goto out;
-
-		ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_END);
-		if (ret && (ret != -FDT_ERR_NOTFOUND))
-			goto out;
-	}
-
-	/* add kaslr-seed */
-	ret = fdt_delprop(dtb, off, FDT_PROP_KASLR_SEED);
-	if (ret == -FDT_ERR_NOTFOUND)
-		ret = 0;
-	else if (ret)
-		goto out;
-
-	if (rng_is_initialized()) {
-		u64 seed = get_random_u64();
-		ret = fdt_setprop_u64(dtb, off, FDT_PROP_KASLR_SEED, seed);
-		if (ret)
-			goto out;
-	} else {
-		pr_notice("RNG is not initialised: omitting \"%s\" property\n",
-				FDT_PROP_KASLR_SEED);
-	}
-
-	/* add rng-seed */
-	if (rng_is_initialized()) {
-		void *rng_seed;
-		ret = fdt_setprop_placeholder(dtb, off, FDT_PROP_RNG_SEED,
-				RNG_SEED_SIZE, &rng_seed);
-		if (ret)
-			goto out;
-		get_random_bytes(rng_seed, RNG_SEED_SIZE);
-	} else {
-		pr_notice("RNG is not initialised: omitting \"%s\" property\n",
-				FDT_PROP_RNG_SEED);
-	}
-
-out:
-	if (ret)
-		return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
-
-	return 0;
-}
-
-/*
- * More space needed so that we can add initrd, bootargs, kaslr-seed,
- * rng-seed, userable-memory-range and elfcorehdr.
- */
-#define DTB_EXTRA_SPACE 0x1000
-
-static int create_dtb(struct kimage *image,
-		      unsigned long initrd_load_addr, unsigned long initrd_len,
-		      char *cmdline, void **dtb)
-{
-	void *buf;
-	size_t buf_size;
-	size_t cmdline_len;
-	int ret;
-
-	cmdline_len = cmdline ? strlen(cmdline) : 0;
-	buf_size = fdt_totalsize(initial_boot_params)
-			+ cmdline_len + DTB_EXTRA_SPACE;
-
-	for (;;) {
-		buf = vmalloc(buf_size);
-		if (!buf)
-			return -ENOMEM;
-
-		/* duplicate a device tree blob */
-		ret = fdt_open_into(initial_boot_params, buf, buf_size);
-		if (ret)
-			return -EINVAL;
-
-		ret = setup_dtb(image, initrd_load_addr, initrd_len,
-				cmdline, buf);
-		if (ret) {
-			vfree(buf);
-			if (ret == -ENOMEM) {
-				/* unlikely, but just in case */
-				buf_size += DTB_EXTRA_SPACE;
-				continue;
-			} else {
-				return ret;
-			}
-		}
-
-		/* trim it */
-		fdt_pack(buf);
-		*dtb = buf;
-
-		return 0;
-	}
-}
-
 static int prepare_elf_headers(void **addr, unsigned long *sz)
 {
 	struct crash_mem *cmem;
@@ -312,12 +145,15 @@ int load_other_segments(struct kimage *image,
 	}
 
 	/* load dtb */
-	ret = create_dtb(image, initrd_load_addr, initrd_len, cmdline, &dtb);
-	if (ret) {
+	dtb = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
+					   initrd_len, cmdline);
+	if (!dtb) {
 		pr_err("Preparing for new dtb failed\n");
 		goto out_err;
 	}
 
+	/* trim it */
+	fdt_pack(dtb);
 	dtb_len = fdt_totalsize(dtb);
 	kbuf.buffer = dtb;
 	kbuf.bufsz = dtb_len;
@@ -341,6 +177,6 @@ int load_other_segments(struct kimage *image,
 
 out_err:
 	image->nr_segments = orig_segments;
-	vfree(dtb);
+	kvfree(dtb);
 	return ret;
 }
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 04/10] powerpc: Use common of_kexec_alloc_and_setup_fdt()
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

From: Rob Herring <robh@kernel.org>

The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".

Use the common of_kexec_alloc_and_setup_fdt() to setup the device tree
and update the memory reservation for kexec for powerpc.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 arch/powerpc/include/asm/kexec.h  |   1 +
 arch/powerpc/kexec/elf_64.c       |  29 ++++---
 arch/powerpc/kexec/file_load.c    | 132 +-----------------------------
 arch/powerpc/kexec/file_load_64.c |   3 +
 4 files changed, 25 insertions(+), 140 deletions(-)

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index dbf09d2f36d0..bdd0ddb9ac4d 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -111,6 +111,7 @@ struct kimage_arch {
 	unsigned long elf_headers_mem;
 	unsigned long elf_headers_sz;
 	void *elf_headers;
+	void *fdt;
 
 #ifdef CONFIG_IMA_KEXEC
 	phys_addr_t ima_buffer_addr;
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index d0e459bb2f05..bfabd06f99b1 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -19,6 +19,7 @@
 #include <linux/kexec.h>
 #include <linux/libfdt.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/slab.h>
 #include <linux/types.h>
@@ -29,7 +30,6 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
 			unsigned long cmdline_len)
 {
 	int ret;
-	unsigned int fdt_size;
 	unsigned long kernel_load_addr;
 	unsigned long initrd_load_addr = 0, fdt_load_addr;
 	void *fdt;
@@ -102,19 +102,13 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
 		pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
 	}
 
-	fdt_size = fdt_totalsize(initial_boot_params) * 2;
-	fdt = kmalloc(fdt_size, GFP_KERNEL);
+	fdt = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
+					   initrd_len, cmdline);
 	if (!fdt) {
 		pr_err("Not enough memory for the device tree.\n");
 		ret = -ENOMEM;
 		goto out;
 	}
-	ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
-	if (ret < 0) {
-		pr_err("Error setting up the new device tree.\n");
-		ret = -EINVAL;
-		goto out;
-	}
 
 	ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr,
 				  initrd_len, cmdline);
@@ -124,13 +118,17 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
 	fdt_pack(fdt);
 
 	kbuf.buffer = fdt;
-	kbuf.bufsz = kbuf.memsz = fdt_size;
+	kbuf.bufsz = kbuf.memsz = fdt_totalsize(fdt);
 	kbuf.buf_align = PAGE_SIZE;
 	kbuf.top_down = true;
 	kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
 	ret = kexec_add_buffer(&kbuf);
 	if (ret)
 		goto out;
+
+	/* FDT will be freed in arch_kimage_file_post_load_cleanup */
+	image->arch.fdt = fdt;
+
 	fdt_load_addr = kbuf.mem;
 
 	pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
@@ -145,8 +143,15 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
 	kfree(modified_cmdline);
 	kexec_free_elf_info(&elf_info);
 
-	/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
-	return ret ? ERR_PTR(ret) : fdt;
+	/*
+	 * Once FDT buffer has been successfully passed to kexec_add_buffer(),
+	 * the FDT buffer address is saved in image->arch.fdt. In that case,
+	 * the memory cannot be freed here in case of any other error.
+	 */
+	if (ret && !image->arch.fdt)
+		kvfree(fdt);
+
+	return ret ? ERR_PTR(ret) : NULL;
 }
 
 const struct kexec_file_ops kexec_elf64_ops = {
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index e452b11df631..d23e2969395c 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -156,135 +156,11 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
 		  unsigned long initrd_load_addr, unsigned long initrd_len,
 		  const char *cmdline)
 {
-	int ret, chosen_node;
-	const void *prop;
-
-	/* Remove memory reservation for the current device tree. */
-	ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
-				 fdt_totalsize(initial_boot_params));
-	if (ret == 0)
-		pr_debug("Removed old device tree reservation.\n");
-	else if (ret != -ENOENT)
-		return ret;
-
-	chosen_node = fdt_path_offset(fdt, "/chosen");
-	if (chosen_node == -FDT_ERR_NOTFOUND) {
-		chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
-					      "chosen");
-		if (chosen_node < 0) {
-			pr_err("Error creating /chosen.\n");
-			return -EINVAL;
-		}
-	} else if (chosen_node < 0) {
-		pr_err("Malformed device tree: error reading /chosen.\n");
-		return -EINVAL;
-	}
-
-	/* Did we boot using an initrd? */
-	prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
-	if (prop) {
-		uint64_t tmp_start, tmp_end, tmp_size;
-
-		tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
-
-		prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
-		if (!prop) {
-			pr_err("Malformed device tree.\n");
-			return -EINVAL;
-		}
-		tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
-
-		/*
-		 * kexec reserves exact initrd size, while firmware may
-		 * reserve a multiple of PAGE_SIZE, so check for both.
-		 */
-		tmp_size = tmp_end - tmp_start;
-		ret = delete_fdt_mem_rsv(fdt, tmp_start, tmp_size);
-		if (ret == -ENOENT)
-			ret = delete_fdt_mem_rsv(fdt, tmp_start,
-						 round_up(tmp_size, PAGE_SIZE));
-		if (ret == 0)
-			pr_debug("Removed old initrd reservation.\n");
-		else if (ret != -ENOENT)
-			return ret;
-
-		/* If there's no new initrd, delete the old initrd's info. */
-		if (initrd_len == 0) {
-			ret = fdt_delprop(fdt, chosen_node,
-					  "linux,initrd-start");
-			if (ret) {
-				pr_err("Error deleting linux,initrd-start.\n");
-				return -EINVAL;
-			}
-
-			ret = fdt_delprop(fdt, chosen_node, "linux,initrd-end");
-			if (ret) {
-				pr_err("Error deleting linux,initrd-end.\n");
-				return -EINVAL;
-			}
-		}
-	}
-
-	if (initrd_len) {
-		ret = fdt_setprop_u64(fdt, chosen_node,
-				      "linux,initrd-start",
-				      initrd_load_addr);
-		if (ret < 0)
-			goto err;
-
-		/* initrd-end is the first address after the initrd image. */
-		ret = fdt_setprop_u64(fdt, chosen_node, "linux,initrd-end",
-				      initrd_load_addr + initrd_len);
-		if (ret < 0)
-			goto err;
-
-		ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
-		if (ret) {
-			pr_err("Error reserving initrd memory: %s\n",
-			       fdt_strerror(ret));
-			return -EINVAL;
-		}
-	}
-
-	if (cmdline != NULL) {
-		ret = fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline);
-		if (ret < 0)
-			goto err;
-	} else {
-		ret = fdt_delprop(fdt, chosen_node, "bootargs");
-		if (ret && ret != -FDT_ERR_NOTFOUND) {
-			pr_err("Error deleting bootargs.\n");
-			return -EINVAL;
-		}
-	}
-
-	if (image->type == KEXEC_TYPE_CRASH) {
-		/*
-		 * Avoid elfcorehdr from being stomped on in kdump kernel by
-		 * setting up memory reserve map.
-		 */
-		ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
-				      image->arch.elf_headers_sz);
-		if (ret) {
-			pr_err("Error reserving elfcorehdr memory: %s\n",
-			       fdt_strerror(ret));
-			goto err;
-		}
-	}
-
-	ret = setup_ima_buffer(image, fdt, chosen_node);
-	if (ret) {
-		pr_err("Error setting up the new device tree.\n");
-		return ret;
-	}
+	int ret;
 
-	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
 	if (ret)
-		goto err;
-
-	return 0;
+		pr_err("Error setting up the new device tree.\n");
 
-err:
-	pr_err("Error setting up the new device tree.\n");
-	return -EINVAL;
+	return ret;
 }
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index a05c19b3cc60..dac3d29c7c77 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -1111,5 +1111,8 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
 	image->arch.elf_headers = NULL;
 	image->arch.elf_headers_sz = 0;
 
+	kvfree(image->arch.fdt);
+	image->arch.fdt = NULL;
+
 	return kexec_image_post_load_cleanup_default(image);
 }
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 05/10] powerpc: Move ima buffer fields to struct kimage
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

The fields ima_buffer_addr and ima_buffer_size in "struct kimage_arch"
for powerpc are used to carry forward the IMA measurement list across
kexec system call.  These fields are not architecture specific, but are
currently limited to powerpc.

arch_ima_add_kexec_buffer() defined in "arch/powerpc/kexec/ima.c"
sets ima_buffer_addr and ima_buffer_size for the kexec system call.
This function does not have architecture specific code, but is
currently limited to powerpc.

Move ima_buffer_addr and ima_buffer_size to "struct kimage".
Rename arch_ima_add_kexec_buffer() to of_ima_add_kexec_buffer()
and move it in drivers/of/kexec.c.

Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Will Deacon <will@kernel.org>
---
 arch/powerpc/include/asm/ima.h     |  3 ---
 arch/powerpc/include/asm/kexec.h   |  5 -----
 arch/powerpc/kexec/ima.c           | 29 ++++++-----------------------
 drivers/of/kexec.c                 | 23 +++++++++++++++++++++++
 include/linux/kexec.h              |  3 +++
 include/linux/of.h                 |  5 +++++
 security/integrity/ima/ima_kexec.c |  3 ++-
 7 files changed, 39 insertions(+), 32 deletions(-)

diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
index ead488cf3981..51f64fd06c19 100644
--- a/arch/powerpc/include/asm/ima.h
+++ b/arch/powerpc/include/asm/ima.h
@@ -14,9 +14,6 @@ static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
 #endif
 
 #ifdef CONFIG_IMA_KEXEC
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
-			      size_t size);
-
 int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
 #else
 static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index bdd0ddb9ac4d..ecf88533d6b4 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -112,11 +112,6 @@ struct kimage_arch {
 	unsigned long elf_headers_sz;
 	void *elf_headers;
 	void *fdt;
-
-#ifdef CONFIG_IMA_KEXEC
-	phys_addr_t ima_buffer_addr;
-	size_t ima_buffer_size;
-#endif
 };
 
 char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
index 720e50e490b6..ed38125e2f87 100644
--- a/arch/powerpc/kexec/ima.c
+++ b/arch/powerpc/kexec/ima.c
@@ -128,23 +128,6 @@ void remove_ima_buffer(void *fdt, int chosen_node)
 }
 
 #ifdef CONFIG_IMA_KEXEC
-/**
- * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
- *
- * Architectures should use this function to pass on the IMA buffer
- * information to the next kernel.
- *
- * Return: 0 on success, negative errno on error.
- */
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
-			      size_t size)
-{
-	image->arch.ima_buffer_addr = load_addr;
-	image->arch.ima_buffer_size = size;
-
-	return 0;
-}
-
 static int write_number(void *p, u64 value, int cells)
 {
 	if (cells == 1) {
@@ -180,7 +163,7 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
 	u8 value[16];
 
 	remove_ima_buffer(fdt, chosen_node);
-	if (!image->arch.ima_buffer_size)
+	if (!image->ima_buffer_size)
 		return 0;
 
 	ret = get_addr_size_cells(&addr_cells, &size_cells);
@@ -192,11 +175,11 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
 	if (entry_size > sizeof(value))
 		return -EINVAL;
 
-	ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
+	ret = write_number(value, image->ima_buffer_addr, addr_cells);
 	if (ret)
 		return ret;
 
-	ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
+	ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
 			   size_cells);
 	if (ret)
 		return ret;
@@ -206,13 +189,13 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
 	if (ret < 0)
 		return -EINVAL;
 
-	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
-			      image->arch.ima_buffer_size);
+	ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
+			      image->ima_buffer_size);
 	if (ret)
 		return -EINVAL;
 
 	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
-		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+		 image->ima_buffer_addr, image->ima_buffer_size);
 
 	return 0;
 }
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 469e09613cdd..9f33d215b9f2 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -63,6 +63,29 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
 	return -ENOENT;
 }
 
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * of_ima_add_kexec_buffer - Add IMA buffer for next kernel
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Use this function to pass on the IMA buffer information to
+ * the next kernel across kexec system call.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int of_ima_add_kexec_buffer(struct kimage *image,
+			    unsigned long load_addr, size_t size)
+{
+	image->ima_buffer_addr = load_addr;
+	image->ima_buffer_size = size;
+
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
+
 /*
  * of_kexec_alloc_and_setup_fdt - Alloc and setup a new Flattened Device Tree
  *
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 5f61389f5f36..75c670f0dfbb 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -304,6 +304,9 @@ struct kimage {
 #ifdef CONFIG_IMA_KEXEC
 	/* Virtual address of IMA measurement buffer for kexec syscall */
 	void *ima_buffer;
+
+	phys_addr_t ima_buffer_addr;
+	size_t ima_buffer_size;
 #endif
 };
 
diff --git a/include/linux/of.h b/include/linux/of.h
index f0eff5e84353..03e0e694be29 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -573,6 +573,11 @@ void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
 				   unsigned long initrd_len,
 				   const char *cmdline);
 
+#ifdef CONFIG_IMA_KEXEC
+int of_ima_add_kexec_buffer(struct kimage *image,
+			    unsigned long load_addr, size_t size);
+#endif /* CONFIG_IMA_KEXEC */
+
 #else /* CONFIG_OF */
 
 static inline void of_core_init(void)
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index e29bea3dd4cc..d346eed2d236 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -10,6 +10,7 @@
 #include <linux/seq_file.h>
 #include <linux/vmalloc.h>
 #include <linux/kexec.h>
+#include <linux/of.h>
 #include "ima.h"
 
 #ifdef CONFIG_IMA_KEXEC
@@ -123,7 +124,7 @@ void ima_add_kexec_buffer(struct kimage *image)
 		return;
 	}
 
-	ret = arch_ima_add_kexec_buffer(image, kbuf.mem, kexec_segment_size);
+	ret = of_ima_add_kexec_buffer(image, kbuf.mem, kexec_segment_size);
 	if (ret) {
 		pr_err("Error passing over kexec measurement buffer.\n");
 		return;
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 06/10] powerpc: Enable passing IMA log to next kernel on kexec
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

CONFIG_HAVE_IMA_KEXEC is enabled to indicate that the IMA measurement
log information is present in the device tree. This should be selected
only if CONFIG_IMA is enabled.

Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
is enabled, to indicate that the IMA measurement log information is
present in the device tree for powerpc.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
 arch/powerpc/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 107bb4319e0e..d6e593ad270e 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -554,7 +554,7 @@ config KEXEC
 config KEXEC_FILE
 	bool "kexec file based system call"
 	select KEXEC_CORE
-	select HAVE_IMA_KEXEC
+	select HAVE_IMA_KEXEC if IMA
 	select BUILD_BIN2C
 	select KEXEC_ELF
 	depends on PPC64
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 07/10] powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up
and freeing the resources required to carry over the IMA measurement
list from the current kernel to the next kernel across kexec system call.
These functions do not have architecture specific code, but are
currently limited to powerpc.

Move remove_ima_buffer() and setup_ima_buffer() calls into
of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".

Move the remaining architecture independent functions from
"arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c".
Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h".
Remove references to the deleted files and functions in powerpc and
in ima.

Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 arch/powerpc/include/asm/ima.h    |  27 ----
 arch/powerpc/include/asm/kexec.h  |   3 -
 arch/powerpc/kexec/Makefile       |   7 -
 arch/powerpc/kexec/file_load.c    |  25 ----
 arch/powerpc/kexec/file_load_64.c |   4 -
 arch/powerpc/kexec/ima.c          | 202 -------------------------
 drivers/of/kexec.c                | 239 ++++++++++++++++++++++++++++++
 include/linux/of.h                |   2 +
 security/integrity/ima/ima.h      |   4 -
 9 files changed, 241 insertions(+), 272 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/ima.h
 delete mode 100644 arch/powerpc/kexec/ima.c

diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
deleted file mode 100644
index 51f64fd06c19..000000000000
--- a/arch/powerpc/include/asm/ima.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_IMA_H
-#define _ASM_POWERPC_IMA_H
-
-struct kimage;
-
-int ima_get_kexec_buffer(void **addr, size_t *size);
-int ima_free_kexec_buffer(void);
-
-#ifdef CONFIG_IMA
-void remove_ima_buffer(void *fdt, int chosen_node);
-#else
-static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
-#endif
-
-#ifdef CONFIG_IMA_KEXEC
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
-#else
-static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
-				   int chosen_node)
-{
-	remove_ima_buffer(fdt, chosen_node);
-	return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
-
-#endif /* _ASM_POWERPC_IMA_H */
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index ecf88533d6b4..2b87993f6e66 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -119,9 +119,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
 int setup_purgatory(struct kimage *image, const void *slave_code,
 		    const void *fdt, unsigned long kernel_load_addr,
 		    unsigned long fdt_load_addr);
-int setup_new_fdt(const struct kimage *image, void *fdt,
-		  unsigned long initrd_load_addr, unsigned long initrd_len,
-		  const char *cmdline);
 int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
 
 #ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
index 4aff6846c772..b6c52608cb49 100644
--- a/arch/powerpc/kexec/Makefile
+++ b/arch/powerpc/kexec/Makefile
@@ -9,13 +9,6 @@ obj-$(CONFIG_PPC32)		+= relocate_32.o
 
 obj-$(CONFIG_KEXEC_FILE)	+= file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
 
-ifdef CONFIG_HAVE_IMA_KEXEC
-ifdef CONFIG_IMA
-obj-y				+= ima.o
-endif
-endif
-
-
 # Disable GCOV, KCOV & sanitizers in odd or sensitive code
 GCOV_PROFILE_core_$(BITS).o := n
 KCOV_INSTRUMENT_core_$(BITS).o := n
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index d23e2969395c..bd8b956aafc3 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -19,7 +19,6 @@
 #include <linux/of_fdt.h>
 #include <linux/libfdt.h>
 #include <asm/setup.h>
-#include <asm/ima.h>
 
 #define SLAVE_CODE_SIZE		256	/* First 0x100 bytes */
 
@@ -140,27 +139,3 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
 
 	return -ENOENT;
 }
-
-/*
- * setup_new_fdt - modify /chosen and memory reservation for the next kernel
- * @image:		kexec image being loaded.
- * @fdt:		Flattened device tree for the next kernel.
- * @initrd_load_addr:	Address where the next initrd will be loaded.
- * @initrd_len:		Size of the next initrd, or 0 if there will be none.
- * @cmdline:		Command line for the next kernel, or NULL if there will
- *			be none.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_new_fdt(const struct kimage *image, void *fdt,
-		  unsigned long initrd_load_addr, unsigned long initrd_len,
-		  const char *cmdline)
-{
-	int ret;
-
-	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
-	if (ret)
-		pr_err("Error setting up the new device tree.\n");
-
-	return ret;
-}
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index dac3d29c7c77..a2b0579f7661 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -944,10 +944,6 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
 	struct crash_mem *umem = NULL, *rmem = NULL;
 	int i, nr_ranges, ret;
 
-	ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
-	if (ret)
-		goto out;
-
 	/*
 	 * Restrict memory usage for kdump kernel by setting up
 	 * usable memory ranges and memory reserve map.
diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
deleted file mode 100644
index ed38125e2f87..000000000000
--- a/arch/powerpc/kexec/ima.c
+++ /dev/null
@@ -1,202 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2016 IBM Corporation
- *
- * Authors:
- * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
- */
-
-#include <linux/slab.h>
-#include <linux/kexec.h>
-#include <linux/of.h>
-#include <linux/memblock.h>
-#include <linux/libfdt.h>
-
-static int get_addr_size_cells(int *addr_cells, int *size_cells)
-{
-	struct device_node *root;
-
-	root = of_find_node_by_path("/");
-	if (!root)
-		return -EINVAL;
-
-	*addr_cells = of_n_addr_cells(root);
-	*size_cells = of_n_size_cells(root);
-
-	of_node_put(root);
-
-	return 0;
-}
-
-static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
-			       size_t *size)
-{
-	int ret, addr_cells, size_cells;
-
-	ret = get_addr_size_cells(&addr_cells, &size_cells);
-	if (ret)
-		return ret;
-
-	if (len < 4 * (addr_cells + size_cells))
-		return -ENOENT;
-
-	*addr = of_read_number(prop, addr_cells);
-	*size = of_read_number(prop + 4 * addr_cells, size_cells);
-
-	return 0;
-}
-
-/**
- * ima_get_kexec_buffer - get IMA buffer from the previous kernel
- * @addr:	On successful return, set to point to the buffer contents.
- * @size:	On successful return, set to the buffer size.
- *
- * Return: 0 on success, negative errno on error.
- */
-int ima_get_kexec_buffer(void **addr, size_t *size)
-{
-	int ret, len;
-	unsigned long tmp_addr;
-	size_t tmp_size;
-	const void *prop;
-
-	prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
-	if (!prop)
-		return -ENOENT;
-
-	ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
-	if (ret)
-		return ret;
-
-	*addr = __va(tmp_addr);
-	*size = tmp_size;
-
-	return 0;
-}
-
-/**
- * ima_free_kexec_buffer - free memory used by the IMA buffer
- */
-int ima_free_kexec_buffer(void)
-{
-	int ret;
-	unsigned long addr;
-	size_t size;
-	struct property *prop;
-
-	prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
-	if (!prop)
-		return -ENOENT;
-
-	ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
-	if (ret)
-		return ret;
-
-	ret = of_remove_property(of_chosen, prop);
-	if (ret)
-		return ret;
-
-	return memblock_free(addr, size);
-
-}
-
-/**
- * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
- *
- * The IMA measurement buffer is of no use to a subsequent kernel, so we always
- * remove it from the device tree.
- */
-void remove_ima_buffer(void *fdt, int chosen_node)
-{
-	int ret, len;
-	unsigned long addr;
-	size_t size;
-	const void *prop;
-
-	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
-	if (!prop)
-		return;
-
-	ret = do_get_kexec_buffer(prop, len, &addr, &size);
-	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
-	if (ret)
-		return;
-
-	ret = delete_fdt_mem_rsv(fdt, addr, size);
-	if (!ret)
-		pr_debug("Removed old IMA buffer reservation.\n");
-}
-
-#ifdef CONFIG_IMA_KEXEC
-static int write_number(void *p, u64 value, int cells)
-{
-	if (cells == 1) {
-		u32 tmp;
-
-		if (value > U32_MAX)
-			return -EINVAL;
-
-		tmp = cpu_to_be32(value);
-		memcpy(p, &tmp, sizeof(tmp));
-	} else if (cells == 2) {
-		u64 tmp;
-
-		tmp = cpu_to_be64(value);
-		memcpy(p, &tmp, sizeof(tmp));
-	} else
-		return -EINVAL;
-
-	return 0;
-}
-
-/**
- * setup_ima_buffer - add IMA buffer information to the fdt
- * @image:		kexec image being loaded.
- * @fdt:		Flattened device tree for the next kernel.
- * @chosen_node:	Offset to the chosen node.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
-{
-	int ret, addr_cells, size_cells, entry_size;
-	u8 value[16];
-
-	remove_ima_buffer(fdt, chosen_node);
-	if (!image->ima_buffer_size)
-		return 0;
-
-	ret = get_addr_size_cells(&addr_cells, &size_cells);
-	if (ret)
-		return ret;
-
-	entry_size = 4 * (addr_cells + size_cells);
-
-	if (entry_size > sizeof(value))
-		return -EINVAL;
-
-	ret = write_number(value, image->ima_buffer_addr, addr_cells);
-	if (ret)
-		return ret;
-
-	ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
-			   size_cells);
-	if (ret)
-		return ret;
-
-	ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
-			  entry_size);
-	if (ret < 0)
-		return -EINVAL;
-
-	ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
-			      image->ima_buffer_size);
-	if (ret)
-		return -EINVAL;
-
-	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
-		 image->ima_buffer_addr, image->ima_buffer_size);
-
-	return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 9f33d215b9f2..c601b5af4a88 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -11,6 +11,7 @@
 
 #include <linux/kernel.h>
 #include <linux/kexec.h>
+#include <linux/memblock.h>
 #include <linux/libfdt.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
@@ -63,6 +64,152 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
 	return -ENOENT;
 }
 
+
+/**
+ * get_addr_size_cells - Get address and size of root node
+ *
+ * @addr_cells: Return address of the root node
+ * @size_cells: Return size of the root node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+	struct device_node *root;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	*addr_cells = of_n_addr_cells(root);
+	*size_cells = of_n_size_cells(root);
+
+	of_node_put(root);
+
+	return 0;
+}
+
+/**
+ * do_get_kexec_buffer - Get address and size of device tree property
+ *
+ * @prop: Device tree property
+ * @len: Size of @prop
+ * @addr: Return address of the node
+ * @size: Return size of the node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+			       size_t *size)
+{
+	int ret, addr_cells, size_cells;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	if (len < 4 * (addr_cells + size_cells))
+		return -ENOENT;
+
+	*addr = of_read_number(prop, addr_cells);
+	*size = of_read_number(prop + 4 * addr_cells, size_cells);
+
+	return 0;
+}
+
+/**
+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
+ *
+ * @fdt: Flattened Device Tree to update
+ * @chosen_node: Offset to the chosen node in the device tree
+ *
+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
+ * remove it from the device tree.
+ */
+static void remove_ima_buffer(void *fdt, int chosen_node)
+{
+	int ret, len;
+	unsigned long addr;
+	size_t size;
+	const void *prop;
+
+	if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+		return;
+
+	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return;
+
+	ret = do_get_kexec_buffer(prop, len, &addr, &size);
+	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
+	if (ret)
+		return;
+
+	ret = fdt_find_and_del_mem_rsv(fdt, addr, size);
+	if (!ret)
+		pr_debug("Removed old IMA buffer reservation.\n");
+}
+
+/**
+ * ima_get_kexec_buffer - get IMA buffer from the previous kernel
+ * @addr:	On successful return, set to point to the buffer contents.
+ * @size:	On successful return, set to the buffer size.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int ima_get_kexec_buffer(void **addr, size_t *size)
+{
+	int ret, len;
+	unsigned long tmp_addr;
+	size_t tmp_size;
+	const void *prop;
+
+	if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+		return -ENOTSUPP;
+
+	prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return -ENOENT;
+
+	ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
+	if (ret)
+		return ret;
+
+	*addr = __va(tmp_addr);
+	*size = tmp_size;
+
+	return 0;
+}
+
+/**
+ * ima_free_kexec_buffer - free memory used by the IMA buffer
+ */
+int ima_free_kexec_buffer(void)
+{
+	int ret;
+	unsigned long addr;
+	size_t size;
+	struct property *prop;
+
+	if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+		return -ENOTSUPP;
+
+	prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
+	if (!prop)
+		return -ENOENT;
+
+	ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
+	if (ret)
+		return ret;
+
+	ret = of_remove_property(of_chosen, prop);
+	if (ret)
+		return ret;
+
+	return memblock_free(addr, size);
+
+}
+
 #ifdef CONFIG_IMA_KEXEC
 /**
  * of_ima_add_kexec_buffer - Add IMA buffer for next kernel
@@ -84,6 +231,93 @@ int of_ima_add_kexec_buffer(struct kimage *image,
 
 	return 0;
 }
+
+/**
+ * write_number - Convert number to big-endian format
+ *
+ * @p:		Buffer to write the number to
+ * @value:	Number to convert
+ * @cells:	Number of cells
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int write_number(void *p, u64 value, int cells)
+{
+	if (cells == 1) {
+		u32 tmp;
+
+		if (value > U32_MAX)
+			return -EINVAL;
+
+		tmp = cpu_to_be32(value);
+		memcpy(p, &tmp, sizeof(tmp));
+	} else if (cells == 2) {
+		u64 tmp;
+
+		tmp = cpu_to_be64(value);
+		memcpy(p, &tmp, sizeof(tmp));
+	} else
+		return -EINVAL;
+
+	return 0;
+}
+
+/**
+ * setup_ima_buffer - add IMA buffer information to the fdt
+ * @image:		kexec image being loaded.
+ * @fdt:		Flattened device tree for the next kernel.
+ * @chosen_node:	Offset to the chosen node.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int setup_ima_buffer(const struct kimage *image, void *fdt,
+			    int chosen_node)
+{
+	int ret, addr_cells, size_cells, entry_size;
+	u8 value[16];
+
+	if (!image->ima_buffer_size)
+		return 0;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	entry_size = 4 * (addr_cells + size_cells);
+
+	if (entry_size > sizeof(value))
+		return -EINVAL;
+
+	ret = write_number(value, image->ima_buffer_addr, addr_cells);
+	if (ret)
+		return ret;
+
+	ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
+			   size_cells);
+	if (ret)
+		return ret;
+
+	ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
+			  entry_size);
+	if (ret < 0)
+		return -EINVAL;
+
+	ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
+			      image->ima_buffer_size);
+	if (ret)
+		return -EINVAL;
+
+	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+		 image->ima_buffer_addr, image->ima_buffer_size);
+
+	return 0;
+}
+#else /* CONFIG_IMA_KEXEC */
+static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
+				   int chosen_node)
+{
+	return 0;
+}
 #endif /* CONFIG_IMA_KEXEC */
 
 /*
@@ -270,6 +504,11 @@ void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
 	}
 
 	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+	if (ret)
+		goto out;
+
+	remove_ima_buffer(fdt, chosen_node);
+	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
 
 out:
 	if (ret) {
diff --git a/include/linux/of.h b/include/linux/of.h
index 03e0e694be29..9041fc286335 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -578,6 +578,8 @@ int of_ima_add_kexec_buffer(struct kimage *image,
 			    unsigned long load_addr, size_t size);
 #endif /* CONFIG_IMA_KEXEC */
 
+int ima_get_kexec_buffer(void **addr, size_t *size);
+int ima_free_kexec_buffer(void);
 #else /* CONFIG_OF */
 
 static inline void of_core_init(void)
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index aa312472c7c5..fdae37fa7051 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -24,10 +24,6 @@
 
 #include "../integrity.h"
 
-#ifdef CONFIG_HAVE_IMA_KEXEC
-#include <asm/ima.h>
-#endif
-
 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
 		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 08/10] kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

fdt_appendprop_addrrange() function adds a property, with the given name,
to the device tree at the given node offset, and also sets the address
and size of the property.  This function should be used to add
"linux,ima-kexec-buffer" property to the device tree and set the address
and size of the IMA measurement buffer, instead of using custom function.

Use fdt_appendprop_addrrange() to add  "linux,ima-kexec-buffer" property
to the device tree.  This property holds the address and size of
the IMA measurement buffer that needs to be passed from the current
kernel to the next kernel across kexec system call.

Remove custom code that is used in setup_ima_buffer() to add
"linux,ima-kexec-buffer" property to the device tree.

Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
 drivers/of/kexec.c | 57 ++++------------------------------------------
 1 file changed, 5 insertions(+), 52 deletions(-)

diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index c601b5af4a88..c53746b9b168 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -232,36 +232,6 @@ int of_ima_add_kexec_buffer(struct kimage *image,
 	return 0;
 }
 
-/**
- * write_number - Convert number to big-endian format
- *
- * @p:		Buffer to write the number to
- * @value:	Number to convert
- * @cells:	Number of cells
- *
- * Return: 0 on success, or negative errno on error.
- */
-static int write_number(void *p, u64 value, int cells)
-{
-	if (cells == 1) {
-		u32 tmp;
-
-		if (value > U32_MAX)
-			return -EINVAL;
-
-		tmp = cpu_to_be32(value);
-		memcpy(p, &tmp, sizeof(tmp));
-	} else if (cells == 2) {
-		u64 tmp;
-
-		tmp = cpu_to_be64(value);
-		memcpy(p, &tmp, sizeof(tmp));
-	} else
-		return -EINVAL;
-
-	return 0;
-}
-
 /**
  * setup_ima_buffer - add IMA buffer information to the fdt
  * @image:		kexec image being loaded.
@@ -273,32 +243,15 @@ static int write_number(void *p, u64 value, int cells)
 static int setup_ima_buffer(const struct kimage *image, void *fdt,
 			    int chosen_node)
 {
-	int ret, addr_cells, size_cells, entry_size;
-	u8 value[16];
+	int ret;
 
 	if (!image->ima_buffer_size)
 		return 0;
 
-	ret = get_addr_size_cells(&addr_cells, &size_cells);
-	if (ret)
-		return ret;
-
-	entry_size = 4 * (addr_cells + size_cells);
-
-	if (entry_size > sizeof(value))
-		return -EINVAL;
-
-	ret = write_number(value, image->ima_buffer_addr, addr_cells);
-	if (ret)
-		return ret;
-
-	ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
-			   size_cells);
-	if (ret)
-		return ret;
-
-	ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
-			  entry_size);
+	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				       "linux,ima-kexec-buffer",
+				       image->ima_buffer_addr,
+				       image->ima_buffer_size);
 	if (ret < 0)
 		return -EINVAL;
 
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 09/10] powerpc: Delete unused function delete_fdt_mem_rsv()
From: Lakshmi Ramasubramanian @ 2021-02-09 18:21 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

delete_fdt_mem_rsv() defined in "arch/powerpc/kexec/file_load.c"
has been renamed to fdt_find_and_del_mem_rsv(), and moved to
"drivers/of/kexec.c".

Remove delete_fdt_mem_rsv() in "arch/powerpc/kexec/file_load.c".

Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 arch/powerpc/include/asm/kexec.h |  1 -
 arch/powerpc/kexec/file_load.c   | 32 --------------------------------
 2 files changed, 33 deletions(-)

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 2b87993f6e66..e543593da1e1 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -119,7 +119,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
 int setup_purgatory(struct kimage *image, const void *slave_code,
 		    const void *fdt, unsigned long kernel_load_addr,
 		    unsigned long fdt_load_addr);
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
 
 #ifdef CONFIG_PPC64
 struct kexec_buf;
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index bd8b956aafc3..6f75a45f14c5 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -107,35 +107,3 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
 
 	return 0;
 }
-
-/**
- * delete_fdt_mem_rsv - delete memory reservation with given address and size
- *
- * Return: 0 on success, or negative errno on error.
- */
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
-{
-	int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
-
-	for (i = 0; i < num_rsvs; i++) {
-		uint64_t rsv_start, rsv_size;
-
-		ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
-		if (ret) {
-			pr_err("Malformed device tree.\n");
-			return -EINVAL;
-		}
-
-		if (rsv_start == start && rsv_size == size) {
-			ret = fdt_del_mem_rsv(fdt, i);
-			if (ret) {
-				pr_err("Error deleting device tree reservation.\n");
-				return -EINVAL;
-			}
-
-			return 0;
-		}
-	}
-
-	return -ENOENT;
-}
-- 
2.30.0


^ permalink raw reply related

* [PATCH v17 10/10] arm64: Enable passing IMA log to next kernel on kexec
From: Lakshmi Ramasubramanian @ 2021-02-09 18:22 UTC (permalink / raw)
  To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
	catalin.marinas, mpe
  Cc: mark.rutland, tao.li, paulus, vincenzo.frascino, frowand.list,
	sashal, masahiroy, jmorris, allison, serge, devicetree,
	pasha.tatashin, prsriva, hsinyi, linux-arm-kernel,
	christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
	linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210209182200.30606-1-nramas@linux.microsoft.com>

Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
is enabled, to indicate that the IMA measurement log information is
present in the device tree for ARM64.

Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
 arch/arm64/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 05e17351e4f3..8a93573cebb6 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1093,6 +1093,7 @@ config KEXEC
 config KEXEC_FILE
 	bool "kexec file based system call"
 	select KEXEC_CORE
+	select HAVE_IMA_KEXEC if IMA
 	help
 	  This is new version of kexec system call. This system call is
 	  file based and takes file descriptors as system call argument
-- 
2.30.0


^ permalink raw reply related

* [PATCH v6 0/2] powerpc/32: Implement C syscall entry/exit (complement)
From: Christophe Leroy @ 2021-02-09 19:29 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, npiggin,
	msuchanek
  Cc: linuxppc-dev, linux-kernel

This series implements C syscall entry/exit for PPC32. It reuses
the work already done for PPC64.

This series is based on today's next-test (f538b53fd47a) where main patchs from v5 are merged in.

The first patch is important for performance.

v6:
- Forced scv param to 0 on syscall_exit_prepare(), and added is_not_scv bool.
- Reworked the last patch to avoid code duplication.

Christophe Leroy (2):
  powerpc/syscall: Do not check unsupported scv vector on PPC32
  powerpc/32: Handle bookE debugging in C in syscall entry/exit

 arch/powerpc/include/asm/interrupt.h | 12 +++++++
 arch/powerpc/include/asm/ptrace.h    |  5 +++
 arch/powerpc/include/asm/reg_booke.h |  3 ++
 arch/powerpc/kernel/entry_32.S       |  7 ----
 arch/powerpc/kernel/head_32.h        | 15 ---------
 arch/powerpc/kernel/head_booke.h     | 19 -----------
 arch/powerpc/kernel/interrupt.c      | 50 ++++++++++++++++++----------
 7 files changed, 52 insertions(+), 59 deletions(-)

-- 
2.25.0


^ permalink raw reply

* [PATCH v6 2/2] powerpc/32: Handle bookE debugging in C in syscall entry/exit
From: Christophe Leroy @ 2021-02-09 19:29 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, npiggin,
	msuchanek
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1612898425.git.christophe.leroy@csgroup.eu>

The handling of SPRN_DBCR0 and other registers can easily
be done in C instead of ASM.

For that, create booke_load_dbcr0() and booke_restore_dbcr0().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v5: New
v6: Refactor into helpers
---
 arch/powerpc/include/asm/interrupt.h | 12 ++++++++
 arch/powerpc/include/asm/reg_booke.h |  3 ++
 arch/powerpc/kernel/entry_32.S       |  7 -----
 arch/powerpc/kernel/head_32.h        | 15 ----------
 arch/powerpc/kernel/head_booke.h     | 19 -------------
 arch/powerpc/kernel/interrupt.c      | 41 ++++++++++++++++++----------
 6 files changed, 42 insertions(+), 55 deletions(-)

diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h
index 4badb3e51c19..e62c37915bbe 100644
--- a/arch/powerpc/include/asm/interrupt.h
+++ b/arch/powerpc/include/asm/interrupt.h
@@ -14,6 +14,18 @@ struct interrupt_state {
 #endif
 };
 
+static inline void booke_restore_dbcr0(void)
+{
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+	unsigned long dbcr0 = current->thread.debug.dbcr0;
+
+	if (IS_ENABLED(CONFIG_PPC32) && unlikely(dbcr0 & DBCR0_IDM)) {
+		mtspr(SPRN_DBSR, -1);
+		mtspr(SPRN_DBCR0, global_dbcr0[smp_processor_id()]);
+	}
+#endif
+}
+
 static inline void interrupt_enter_prepare(struct pt_regs *regs, struct interrupt_state *state)
 {
 	/*
diff --git a/arch/powerpc/include/asm/reg_booke.h b/arch/powerpc/include/asm/reg_booke.h
index 262782f08fd4..17b8dcd9a40d 100644
--- a/arch/powerpc/include/asm/reg_booke.h
+++ b/arch/powerpc/include/asm/reg_booke.h
@@ -691,6 +691,9 @@
 #define mttmr(rn, v)	asm volatile(MTTMR(rn, %0) : \
 				     : "r" ((unsigned long)(v)) \
 				     : "memory")
+
+extern unsigned long global_dbcr0[];
+
 #endif /* !__ASSEMBLY__ */
 
 #endif /* __ASM_POWERPC_REG_BOOKE_H__ */
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 9dd90be9f8a5..78c430b7f9d9 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -343,13 +343,6 @@ ret_from_syscall:
 	addi    r4,r1,STACK_FRAME_OVERHEAD
 	li	r5,0
 	bl	syscall_exit_prepare
-#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
-	/* If the process has its own DBCR0 value, load it up.  The internal
-	   debug mode bit tells us that dbcr0 should be loaded. */
-	lwz	r0,THREAD+THREAD_DBCR0(r2)
-	andis.	r10,r0,DBCR0_IDM@h
-	bnel-	load_dbcr0
-#endif
 #ifdef CONFIG_PPC_47x
 	lis	r4,icache_44x_need_flush@ha
 	lwz	r5,icache_44x_need_flush@l(r4)
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 1afad7bc3395..5d4706c14572 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -153,21 +153,6 @@
 	SAVE_4GPRS(3, r11)
 	SAVE_2GPRS(7, r11)
 	addi	r2,r12,-THREAD
-#if defined(CONFIG_40x)
-	/* Check to see if the dbcr0 register is set up to debug.  Use the
-	   internal debug mode bit to do this. */
-	lwz	r12,THREAD_DBCR0(r12)
-	andis.	r12,r12,DBCR0_IDM@h
-	beq+	3f
-	/* From user and task is ptraced - load up global dbcr0 */
-	li	r12,-1			/* clear all pending debug events */
-	mtspr	SPRN_DBSR,r12
-	lis	r11,global_dbcr0@ha
-	addi	r11,r11,global_dbcr0@l
-	lwz	r12,0(r11)
-	mtspr	SPRN_DBCR0,r12
-3:
-#endif
 	b	transfer_to_syscall		/* jump to handler */
 .endm
 
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 5f565232b99d..47857795f50a 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -130,25 +130,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
 	SAVE_2GPRS(7, r11)
 
 	addi	r2,r10,-THREAD
-	/* Check to see if the dbcr0 register is set up to debug.  Use the
-	   internal debug mode bit to do this. */
-	lwz	r12,THREAD_DBCR0(r10)
-	andis.	r12,r12,DBCR0_IDM@h
-	beq+	3f
-	/* From user and task is ptraced - load up global dbcr0 */
-	li	r12,-1			/* clear all pending debug events */
-	mtspr	SPRN_DBSR,r12
-	lis	r11,global_dbcr0@ha
-	addi	r11,r11,global_dbcr0@l
-#ifdef CONFIG_SMP
-	lwz	r10, TASK_CPU(r2)
-	slwi	r10, r10, 2
-	add	r11, r11, r10
-#endif
-	lwz	r12,0(r11)
-	mtspr	SPRN_DBCR0,r12
-
-3:
 	b	transfer_to_syscall	/* jump to handler */
 .endm
 
diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
index 75d657b63332..f93664ad4a5e 100644
--- a/arch/powerpc/kernel/interrupt.c
+++ b/arch/powerpc/kernel/interrupt.c
@@ -73,6 +73,8 @@ notrace long system_call_exception(long r3, long r4, long r5,
 		kuap_check_amr();
 #endif
 
+	booke_restore_dbcr0();
+
 	account_cpu_user_entry();
 
 	account_stolen_time();
@@ -204,6 +206,28 @@ static notrace inline bool prep_irq_for_enabled_exit(bool clear_ri, bool irqs_en
 	return false;
 }
 
+static notrace void booke_load_dbcr0(void)
+{
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+	unsigned long dbcr0 = current->thread.debug.dbcr0;
+
+	if (likely(!(dbcr0 & DBCR0_IDM)))
+		return;
+
+	/*
+	 * Check to see if the dbcr0 register is set up to debug.
+	 * Use the internal debug mode bit to do this.
+	 */
+	mtmsr(mfmsr() & ~MSR_DE);
+	if (IS_ENABLED(CONFIG_PPC32)) {
+		isync();
+		global_dbcr0[smp_processor_id()] = mfspr(SPRN_DBCR0);
+	}
+	mtspr(SPRN_DBCR0, dbcr0);
+	mtspr(SPRN_DBSR, -1);
+#endif
+}
+
 /*
  * This should be called after a syscall returns, with r3 the return value
  * from the syscall. If this function returns non-zero, the system call
@@ -317,6 +341,8 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 	local_paca->tm_scratch = regs->msr;
 #endif
 
+	booke_load_dbcr0();
+
 	account_cpu_user_exit();
 
 #ifdef CONFIG_PPC_BOOK3S_64 /* BOOK3E and ppc32 not using this */
@@ -331,9 +357,6 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 #ifndef CONFIG_PPC_BOOK3E_64 /* BOOK3E not yet using this */
 notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned long msr)
 {
-#ifdef CONFIG_PPC_BOOK3E
-	struct thread_struct *ts = &current->thread;
-#endif
 	unsigned long *ti_flagsp = &current_thread_info()->flags;
 	unsigned long ti_flags;
 	unsigned long flags;
@@ -398,17 +421,7 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned
 		goto again;
 	}
 
-#ifdef CONFIG_PPC_BOOK3E
-	if (unlikely(ts->debug.dbcr0 & DBCR0_IDM)) {
-		/*
-		 * Check to see if the dbcr0 register is set up to debug.
-		 * Use the internal debug mode bit to do this.
-		 */
-		mtmsr(mfmsr() & ~MSR_DE);
-		mtspr(SPRN_DBCR0, ts->debug.dbcr0);
-		mtspr(SPRN_DBSR, -1);
-	}
-#endif
+	booke_load_dbcr0();
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	local_paca->tm_scratch = regs->msr;
-- 
2.25.0


^ permalink raw reply related

* [PATCH v6 1/2] powerpc/syscall: Do not check unsupported scv vector on PPC32
From: Christophe Leroy @ 2021-02-09 19:29 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, npiggin,
	msuchanek
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1612898425.git.christophe.leroy@csgroup.eu>

Only book3s/64 has scv. No need to check the 0x7ff0 trap on 32 or 64e.
For that, add a helper trap_is_unsupported_scv() similar to
trap_is_scv().

And ignore the scv parameter in syscall_exit_prepare (Save 14 cycles
346 => 332 cycles)

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v5: Added a helper trap_is_unsupported_scv()
v6: Still set r5 when calling syscall_exit_prepare() and introduce a local bool 'is_not_scv'
---
 arch/powerpc/include/asm/ptrace.h | 5 +++++
 arch/powerpc/kernel/interrupt.c   | 9 +++++----
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 8236c5e749e4..975ba260006a 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -232,6 +232,11 @@ static inline bool trap_is_scv(struct pt_regs *regs)
 	return (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && TRAP(regs) == 0x3000);
 }
 
+static inline bool trap_is_unsupported_scv(struct pt_regs *regs)
+{
+	return IS_ENABLED(CONFIG_PPC_BOOK3S_64) && TRAP(regs) == 0x7ff0;
+}
+
 static inline bool trap_is_syscall(struct pt_regs *regs)
 {
 	return (trap_is_scv(regs) || TRAP(regs) == 0xc00);
diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
index 107ec39f05cb..75d657b63332 100644
--- a/arch/powerpc/kernel/interrupt.c
+++ b/arch/powerpc/kernel/interrupt.c
@@ -88,7 +88,7 @@ notrace long system_call_exception(long r3, long r4, long r5,
 	local_irq_enable();
 
 	if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) {
-		if (unlikely(regs->trap == 0x7ff0)) {
+		if (unlikely(trap_is_unsupported_scv(regs))) {
 			/* Unsupported scv vector */
 			_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
 			return regs->gpr[3];
@@ -111,7 +111,7 @@ notrace long system_call_exception(long r3, long r4, long r5,
 		r8 = regs->gpr[8];
 
 	} else if (unlikely(r0 >= NR_syscalls)) {
-		if (unlikely(regs->trap == 0x7ff0)) {
+		if (unlikely(trap_is_unsupported_scv(regs))) {
 			/* Unsupported scv vector */
 			_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
 			return regs->gpr[3];
@@ -220,6 +220,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 	unsigned long *ti_flagsp = &current_thread_info()->flags;
 	unsigned long ti_flags;
 	unsigned long ret = 0;
+	bool is_not_scv = !IS_ENABLED(CONFIG_PPC_BOOK3S_64) || !scv;
 
 	CT_WARN_ON(ct_state() == CONTEXT_USER);
 
@@ -234,7 +235,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 
 	ti_flags = *ti_flagsp;
 
-	if (unlikely(r3 >= (unsigned long)-MAX_ERRNO) && !scv) {
+	if (unlikely(r3 >= (unsigned long)-MAX_ERRNO) && is_not_scv) {
 		if (likely(!(ti_flags & (_TIF_NOERROR | _TIF_RESTOREALL)))) {
 			r3 = -r3;
 			regs->ccr |= 0x10000000; /* Set SO bit in CR */
@@ -305,7 +306,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 	user_enter_irqoff();
 
 	/* scv need not set RI=0 because SRRs are not used */
-	if (unlikely(!__prep_irq_for_enabled_exit(!scv))) {
+	if (unlikely(!__prep_irq_for_enabled_exit(is_not_scv))) {
 		user_exit_irqoff();
 		local_irq_enable();
 		local_irq_disable();
-- 
2.25.0


^ permalink raw reply related

* [powerpc:next-test 129/159] arch/powerpc/mm/book3s64/radix_tlb.c:646:6: warning: no previous prototype for function 'exit_lazy_flush_tlb'
From: kernel test robot @ 2021-02-09 20:15 UTC (permalink / raw)
  To: Nicholas Piggin; +Cc: clang-built-linux, kbuild-all, linuxppc-dev

[-- Attachment #1: Type: text/plain, Size: 3772 bytes --]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next-test
head:   5811244192fc4e18c001c69300044c2acf30bd91
commit: 032b7f08932c9b212952d6d585e45b2941b3e8be [129/159] powerpc/64s/radix: serialize_against_pte_lookup IPIs trim mm_cpumask
config: powerpc-randconfig-r026-20210209 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project c9439ca36342fb6013187d0a69aef92736951476)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install powerpc cross compiling tool for clang build
        # apt-get install binutils-powerpc-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id=032b7f08932c9b212952d6d585e45b2941b3e8be
        git remote add powerpc https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git
        git fetch --no-tags powerpc next-test
        git checkout 032b7f08932c9b212952d6d585e45b2941b3e8be
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> arch/powerpc/mm/book3s64/radix_tlb.c:646:6: warning: no previous prototype for function 'exit_lazy_flush_tlb' [-Wmissing-prototypes]
   void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush)
        ^
   arch/powerpc/mm/book3s64/radix_tlb.c:646:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush)
   ^
   static 
   1 warning generated.


vim +/exit_lazy_flush_tlb +646 arch/powerpc/mm/book3s64/radix_tlb.c

   641	
   642	/*
   643	 * If always_flush is true, then flush even if this CPU can't be removed
   644	 * from mm_cpumask.
   645	 */
 > 646	void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush)
   647	{
   648		unsigned long pid = mm->context.id;
   649		int cpu = smp_processor_id();
   650	
   651		/*
   652		 * A kthread could have done a mmget_not_zero() after the flushing CPU
   653		 * checked mm_cpumask, and be in the process of kthread_use_mm when
   654		 * interrupted here. In that case, current->mm will be set to mm,
   655		 * because kthread_use_mm() setting ->mm and switching to the mm is
   656		 * done with interrupts off.
   657		 */
   658		if (current->mm == mm)
   659			goto out;
   660	
   661		if (current->active_mm == mm) {
   662			WARN_ON_ONCE(current->mm != NULL);
   663			/* Is a kernel thread and is using mm as the lazy tlb */
   664			mmgrab(&init_mm);
   665			current->active_mm = &init_mm;
   666			switch_mm_irqs_off(mm, &init_mm, current);
   667			mmdrop(mm);
   668		}
   669	
   670		/*
   671		 * This IPI may be initiated from any source including those not
   672		 * running the mm, so there may be a racing IPI that comes after
   673		 * this one which finds the cpumask already clear. Check and avoid
   674		 * underflowing the active_cpus count in that case. The race should
   675		 * not otherwise be a problem, but the TLB must be flushed because
   676		 * that's what the caller expects.
   677		 */
   678		if (cpumask_test_cpu(cpu, mm_cpumask(mm))) {
   679			atomic_dec(&mm->context.active_cpus);
   680			cpumask_clear_cpu(cpu, mm_cpumask(mm));
   681			always_flush = true;
   682		}
   683	
   684	out:
   685		if (always_flush)
   686			_tlbiel_pid(pid, RIC_FLUSH_ALL);
   687	}
   688	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 35355 bytes --]

^ permalink raw reply

* Re: [PATCH v5 10/10] powerpc/signal64: Use __get_user() to copy sigset_t
From: Christophe Leroy @ 2021-02-09 21:45 UTC (permalink / raw)
  To: Christopher M. Riedl; +Cc: linuxppc-dev
In-Reply-To: <20210203184323.20792-11-cmr@codefail.de>

"Christopher M. Riedl" <cmr@codefail.de> a écrit :

> Usually sigset_t is exactly 8B which is a "trivial" size and does not
> warrant using __copy_from_user(). Use __get_user() directly in
> anticipation of future work to remove the trivial size optimizations
> from __copy_from_user(). Calling __get_user() also results in a small
> boost to signal handling throughput here.
>
> Signed-off-by: Christopher M. Riedl <cmr@codefail.de>
> ---
>  arch/powerpc/kernel/signal_64.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/kernel/signal_64.c  
> b/arch/powerpc/kernel/signal_64.c
> index 817b64e1e409..42fdc4a7ff72 100644
> --- a/arch/powerpc/kernel/signal_64.c
> +++ b/arch/powerpc/kernel/signal_64.c
> @@ -97,6 +97,14 @@ static void prepare_setup_sigcontext(struct  
> task_struct *tsk, int ctx_has_vsx_re
>  #endif /* CONFIG_VSX */
>  }
>
> +static inline int get_user_sigset(sigset_t *dst, const sigset_t *src)

Should be called __get_user_sigset() as it is a helper for __get_user()

> +{
> +	if (sizeof(sigset_t) <= 8)

We should always use __get_user(), see below.

> +		return __get_user(dst->sig[0], &src->sig[0]);

I think the above will not work on ppc32, it will only copy 4 bytes.
You must cast the source to u64*

> +	else
> +		return __copy_from_user(dst, src, sizeof(sigset_t));

I see no point in keeping this alternative. Today sigset_ t is fixed.
If you fear one day someone might change it to something different  
than a u64, just add a BUILD_BUG_ON(sizeof(sigset_t) != sizeof(u64));

> +}
> +
>  /*
>   * Set up the sigcontext for the signal frame.
>   */
> @@ -701,8 +709,9 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext  
> __user *, old_ctx,
>  	 * We kill the task with a SIGSEGV in this situation.
>  	 */
>
> -	if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
> +	if (get_user_sigset(&set, &new_ctx->uc_sigmask))
>  		do_exit(SIGSEGV);
> +

This white space is not part of the change, keep patches to the  
minimum, avoid cosmetic

>  	set_current_blocked(&set);
>
>  	if (!user_read_access_begin(new_ctx, ctx_size))
> @@ -740,8 +749,9 @@ SYSCALL_DEFINE0(rt_sigreturn)
>  	if (!access_ok(uc, sizeof(*uc)))
>  		goto badframe;
>
> -	if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
> +	if (get_user_sigset(&set, &uc->uc_sigmask))
>  		goto badframe;
> +

Same

>  	set_current_blocked(&set);
>
>  #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
> --
> 2.26.1



^ permalink raw reply

* [powerpc:next-test 67/159] arch/powerpc/platforms/83xx/km83xx.c:183:19: error: 'mpc83xx_setup_pci' undeclared here (not in a function); did you mean
From: kernel test robot @ 2021-02-09 22:08 UTC (permalink / raw)
  To: Oliver O'Halloran; +Cc: linuxppc-dev, kbuild-all

[-- Attachment #1: Type: text/plain, Size: 1779 bytes --]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next-test
head:   5811244192fc4e18c001c69300044c2acf30bd91
commit: 83f84041ff1cf6c23fc38861218af2d4ca2d9b38 [67/159] powerpc/83xx: Move PHB discovery
config: powerpc-kmeter1_defconfig (attached as .config)
compiler: powerpc-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id=83f84041ff1cf6c23fc38861218af2d4ca2d9b38
        git remote add powerpc https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git
        git fetch --no-tags powerpc next-test
        git checkout 83f84041ff1cf6c23fc38861218af2d4ca2d9b38
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> arch/powerpc/platforms/83xx/km83xx.c:183:19: error: 'mpc83xx_setup_pci' undeclared here (not in a function); did you mean 'mpc83xx_setup_arch'?
     183 |  .discover_phbs = mpc83xx_setup_pci,
         |                   ^~~~~~~~~~~~~~~~~
         |                   mpc83xx_setup_arch


vim +183 arch/powerpc/platforms/83xx/km83xx.c

   178	
   179	define_machine(mpc83xx_km) {
   180		.name		= "mpc83xx-km-platform",
   181		.probe		= mpc83xx_km_probe,
   182		.setup_arch	= mpc83xx_km_setup_arch,
 > 183		.discover_phbs	= mpc83xx_setup_pci,

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 13134 bytes --]

^ permalink raw reply

* Re: [PATCH v2 2/7] ASoC: fsl_rpmsg: Add CPU DAI driver for audio base on rpmsg
From: Mark Brown @ 2021-02-09 22:29 UTC (permalink / raw)
  To: Shengjiu Wang
  Cc: open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	alsa-devel, Timur Tabi, Xiubo Li, Fabio Estevam, Shengjiu Wang,
	Takashi Iwai, Liam Girdwood, linux-kernel, Nicolin Chen,
	Rob Herring, linuxppc-dev
In-Reply-To: <CAA+D8AMRGRRk6FzdiqaHAP1=dPJngNgmdGmU59vrroXA9BMyXw@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 427 bytes --]

On Tue, Feb 09, 2021 at 05:16:16PM +0800, Shengjiu Wang wrote:
> On Mon, Feb 8, 2021 at 7:53 PM Mark Brown <broonie@kernel.org> wrote:

> > hw_params() can be called multiple times and there's no need for it to
> > be balanced with hw_free(), I'd move this to a different callback (DAPM
> > should work well).

> Which callback should I use? Is there an example?

Like I say I'd actually recommend moving this control to DAPM.

[-- Attachment #2: signature.asc --]
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^ permalink raw reply

* Re: [PATCH 1/3] spi: mpc52xx: Avoid using get_tbl()
From: Mark Brown @ 2021-02-09 22:30 UTC (permalink / raw)
  To: Christophe Leroy; +Cc: linux-kernel, linux-spi, Paul Mackerras, linuxppc-dev
In-Reply-To: <99bf008e2970de7f8ed3225cda69a6d06ae1a644.1612866360.git.christophe.leroy@csgroup.eu>

[-- Attachment #1: Type: text/plain, Size: 333 bytes --]

On Tue, Feb 09, 2021 at 10:26:21AM +0000, Christophe Leroy wrote:
> get_tbl() is confusing as it returns the content TBL register
> on PPC32 but the concatenation of TBL and TBU on PPC64.
> 
> Use mftb() instead.
> 
> This will allow the removal of get_tbl() in a following patch.

Acked-by: Mark Brown <broonie@kernel.org>

[-- Attachment #2: signature.asc --]
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^ permalink raw reply


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