Re: [PATCH v3 2/2] remoteproc: Add elf64 support in elf loader

Clément Leger
2020-02-07T07:57:09Z

----- On 6 Feb, 2020, at 18:48, Mathieu Poirier mathieu.poirier@linaro.org wrote:

> On Thu, Feb 06, 2020 at 04:05:44PM +0100, Clément Leger wrote:
>> Hi Mathieu,
>>
>> ----- On 6 Feb, 2020, at 09:37, Clément Leger cleger@kalray.eu wrote:
>>
>> > Hi Mathieu,
>> >
>> > ----- On 5 Feb, 2020, at 23:49, Mathieu Poirier mathieu.poirier@linaro.org
>> > wrote:
>> >
>> >> On Tue, Feb 04, 2020 at 06:44:12PM +0100, Clement Leger wrote:
>> >>> elf32 and elf64 mainly differ by their types. In order to avoid
>> >>> copy/pasting the whole loader code, generate static inline functions
>> >>> which will access values according to the elf class. It allows to keep a
>> >>> common loader basis.
>> >>> In order to accommodate both elf types sizes, the maximum size for a
>> >>> elf header member is chosen using the maximum value of both elf class.
>> >>>
>> >>> Signed-off-by: Clement Leger <cleger@kalray.eu>
>> >>> Tested-by: Arnaud POULIQUEN <arnaud.pouliquen@st.com>
>> >>> ---
>> >>> Documentation/remoteproc.txt | 2 +-
>> >>> drivers/remoteproc/remoteproc_elf_loader.c | 147 ++++++++++++++++++-----------
>> >>> drivers/remoteproc/remoteproc_elf_loader.h | 69 ++++++++++++++
>> >>> drivers/remoteproc/remoteproc_internal.h | 2 +-
>> >>> drivers/remoteproc/st_remoteproc.c | 2 +-
>> >>> include/linux/remoteproc.h | 4 +-
>> >>> 6 files changed, 167 insertions(+), 59 deletions(-)
>> >>> create mode 100644 drivers/remoteproc/remoteproc_elf_loader.h
>> >>>
>> >>> diff --git a/Documentation/remoteproc.txt b/Documentation/remoteproc.txt
>> >>> index 03c3d2e568b0..2be1147256e0 100644
>> >>> --- a/Documentation/remoteproc.txt
>> >>> +++ b/Documentation/remoteproc.txt
>> >>> @@ -230,7 +230,7 @@ in the used rings.
>> >>> Binary Firmware Structure
>> >>> =========================
>> >>>
>> >>> -At this point remoteproc only supports ELF32 firmware binaries. However,
>> >>> +At this point remoteproc supports ELF32 and ELF64 firmware binaries. However,
>> >>> it is quite expected that other platforms/devices which we'd want to
>> >>> support with this framework will be based on different binary formats.
>> >>>
>> >>> diff --git a/drivers/remoteproc/remoteproc_elf_loader.c
>> >>> b/drivers/remoteproc/remoteproc_elf_loader.c
>> >>> index 606aae166eba..21fd2b2fe5ae 100644
>> >>> --- a/drivers/remoteproc/remoteproc_elf_loader.c
>> >>> +++ b/drivers/remoteproc/remoteproc_elf_loader.c
>> >>> @@ -23,6 +23,7 @@
>> >>> #include <linux/elf.h>
>> >>>
>> >>> #include "remoteproc_internal.h"
>> >>> +#include "remoteproc_elf_loader.h"
>> >>>
>> >>> /**
>> >>> * rproc_elf_sanity_check() - Sanity Check ELF firmware image
>> >>> @@ -35,8 +36,16 @@ int rproc_elf_sanity_check(struct rproc *rproc, const struct
>> >>> firmware *fw)
>> >>> {
>> >>> const char *name = rproc->firmware;
>> >>> struct device *dev = &rproc->dev;
>> >>> + /*
>> >>> + * Elf files are beginning with the same structure. Thus, to simplify
>> >>> + * header parsing, we can use the elf32_hdr one for both elf64 and
>> >>> + * elf32.
>> >>> + */
>> >>> struct elf32_hdr *ehdr;
>> >>> + u32 elf_shdr_size;
>> >>> + u64 phoff, shoff;
>> >>> char class;
>> >>> + u16 phnum;
>> >>>
>> >>> if (!fw) {
>> >>> dev_err(dev, "failed to load %s\n", name);
>> >>> @@ -50,13 +59,22 @@ int rproc_elf_sanity_check(struct rproc *rproc, const struct
>> >>> firmware *fw)
>> >>>
>> >>> ehdr = (struct elf32_hdr *)fw->data;
>> >>>
>> >>> - /* We only support ELF32 at this point */
>> >>> + if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
>> >>> + dev_err(dev, "Image is corrupted (bad magic)\n");
>> >>> + return -EINVAL;
>> >>> + }
>> >>> +
>> >>> class = ehdr->e_ident[EI_CLASS];
>> >>> - if (class != ELFCLASS32) {
>> >>> + if (class != ELFCLASS32 && class != ELFCLASS64) {
>> >>> dev_err(dev, "Unsupported class: %d\n", class);
>> >>> return -EINVAL;
>> >>> }
>> >>>
>> >>> + if (class == ELFCLASS64 && fw->size < sizeof(struct elf64_hdr)) {
>> >>> + dev_err(dev, "elf64 header is too small\n");
>> >>> + return -EINVAL;
>> >>> + }
>> >>> +
>> >>> /* We assume the firmware has the same endianness as the host */
>> >>> # ifdef __LITTLE_ENDIAN
>> >>> if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB) {
>> >>> @@ -67,26 +85,29 @@ int rproc_elf_sanity_check(struct rproc *rproc, const struct
>> >>> firmware *fw)
>> >>> return -EINVAL;
>> >>> }
>> >>>
>> >>> - if (fw->size < ehdr->e_shoff + sizeof(struct elf32_shdr)) {
>> >>> - dev_err(dev, "Image is too small\n");
>> >>> - return -EINVAL;
>> >>> - }
>> >>> + phoff = elf_hdr_e_phoff(class, fw->data);
>> >>> + shoff = elf_hdr_e_shoff(class, fw->data);
>> >>> + phnum = elf_hdr_e_phnum(class, fw->data);
>> >>> + elf_shdr_size = elf_size_of_shdr(class);
>> >>>
>> >>> - if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
>> >>> - dev_err(dev, "Image is corrupted (bad magic)\n");
>> >>> + if (fw->size < shoff + elf_shdr_size) {
>> >>> + dev_err(dev, "Image is too small\n");
>> >>> return -EINVAL;
>> >>> }
>> >>>
>> >>> - if (ehdr->e_phnum == 0) {
>> >>> + if (phnum == 0) {
>> >>> dev_err(dev, "No loadable segments\n");
>> >>> return -EINVAL;
>> >>> }
>> >>>
>> >>> - if (ehdr->e_phoff > fw->size) {
>> >>> + if (phoff > fw->size) {
>> >>> dev_err(dev, "Firmware size is too small\n");
>> >>> return -EINVAL;
>> >>> }
>> >>>
>> >>> + dev_dbg(dev, "Firmware is an elf%d file\n",
>> >>> + class == ELFCLASS32 ? 32 : 64);
>> >>> +
>> >>> return 0;
>> >>> }
>> >>> EXPORT_SYMBOL(rproc_elf_sanity_check);
>> >>> @@ -102,11 +123,9 @@ EXPORT_SYMBOL(rproc_elf_sanity_check);
>> >>> * Note that the boot address is not a configurable property of all remote
>> >>> * processors. Some will always boot at a specific hard-coded address.
>> >>> */
>> >>> -u32 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw)
>> >>> +u64 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw)
>> >>> {
>> >>> - struct elf32_hdr *ehdr = (struct elf32_hdr *)fw->data;
>> >>> -
>> >>> - return ehdr->e_entry;
>> >>> + return elf_hdr_e_entry(fw_elf_get_class(fw), fw->data);
>> >>> }
>> >>> EXPORT_SYMBOL(rproc_elf_get_boot_addr);
>> >>>
>> >>> @@ -137,37 +156,41 @@ EXPORT_SYMBOL(rproc_elf_get_boot_addr);
>> >>> int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw)
>> >>> {
>> >>> struct device *dev = &rproc->dev;
>> >>> - struct elf32_hdr *ehdr;
>> >>> - struct elf32_phdr *phdr;
>> >>> + const void *ehdr, *phdr;
>> >>> int i, ret = 0;
>> >>> + u16 phnum;
>> >>> const u8 *elf_data = fw->data;
>> >>> + u8 class = fw_elf_get_class(fw);
>> >>> + u32 elf_phdr_size = elf_size_of_phdr(class);
>> >>>
>> >>> - ehdr = (struct elf32_hdr *)elf_data;
>> >>> - phdr = (struct elf32_phdr *)(elf_data + ehdr->e_phoff);
>> >>> + ehdr = elf_data;
>> >>> + phnum = elf_hdr_e_phnum(class, ehdr);
>> >>> + phdr = elf_data + elf_hdr_e_phoff(class, ehdr);
>> >>>
>> >>> /* go through the available ELF segments */
>> >>> - for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
>> >>> - u32 da = phdr->p_paddr;
>> >>> - u32 memsz = phdr->p_memsz;
>> >>> - u32 filesz = phdr->p_filesz;
>> >>> - u32 offset = phdr->p_offset;
>> >>> + for (i = 0; i < phnum; i++, phdr += elf_phdr_size) {
>> >>> + u64 da = elf_phdr_p_paddr(class, phdr);
>> >>> + u64 memsz = elf_phdr_p_memsz(class, phdr);
>> >>> + u64 filesz = elf_phdr_p_filesz(class, phdr);
>> >>> + u64 offset = elf_phdr_p_offset(class, phdr);
>> >>> + u32 type = elf_phdr_p_type(class, phdr);
>> >>> void *ptr;
>> >>>
>> >>> - if (phdr->p_type != PT_LOAD)
>> >>> + if (type != PT_LOAD)
>> >>> continue;
>> >>>
>> >>> - dev_dbg(dev, "phdr: type %d da 0x%x memsz 0x%x filesz 0x%x\n",
>> >>> - phdr->p_type, da, memsz, filesz);
>> >>> + dev_dbg(dev, "phdr: type %d da 0x%llx memsz 0x%llx filesz 0x%llx\n",
>> >>> + type, da, memsz, filesz);
>> >>>
>> >>> if (filesz > memsz) {
>> >>> - dev_err(dev, "bad phdr filesz 0x%x memsz 0x%x\n",
>> >>> + dev_err(dev, "bad phdr filesz 0x%llx memsz 0x%llx\n",
>> >>> filesz, memsz);
>> >>> ret = -EINVAL;
>> >>> break;
>> >>> }
>> >>>
>> >>> if (offset + filesz > fw->size) {
>> >>> - dev_err(dev, "truncated fw: need 0x%x avail 0x%zx\n",
>> >>> + dev_err(dev, "truncated fw: need 0x%llx avail 0x%zx\n",
>> >>> offset + filesz, fw->size);
>> >>> ret = -EINVAL;
>> >>> break;
>> >>> @@ -176,14 +199,15 @@ int rproc_elf_load_segments(struct rproc *rproc, const
>> >>> struct firmware *fw)
>> >>> /* grab the kernel address for this device address */
>> >>> ptr = rproc_da_to_va(rproc, da, memsz);
>> >>> if (!ptr) {
>> >>> - dev_err(dev, "bad phdr da 0x%x mem 0x%x\n", da, memsz);
>> >>> + dev_err(dev, "bad phdr da 0x%llx mem 0x%llx\n", da,
>> >>> + memsz);
>> >>> ret = -EINVAL;
>> >>> break;
>> >>> }
>> >>>
>> >>> /* put the segment where the remote processor expects it */
>> >>> - if (phdr->p_filesz)
>> >>> - memcpy(ptr, elf_data + phdr->p_offset, filesz);
>> >>> + if (filesz)
>> >>> + memcpy(ptr, elf_data + offset, filesz);
>> >>>
>> >>> /*
>> >>> * Zero out remaining memory for this segment.
>> >>> @@ -200,24 +224,35 @@ int rproc_elf_load_segments(struct rproc *rproc, const
>> >>> struct firmware *fw)
>> >>> }
>> >>> EXPORT_SYMBOL(rproc_elf_load_segments);
>> >>>
>> >>> -static struct elf32_shdr *
>> >>> -find_table(struct device *dev, struct elf32_hdr *ehdr, size_t fw_size)
>> >>> +static const void *
>> >>> +find_table(struct device *dev, const struct firmware *fw)
>> >>> {
>> >>> - struct elf32_shdr *shdr;
>> >>> + const void *shdr, *name_table_shdr;
>> >>> int i;
>> >>> const char *name_table;
>> >>> struct resource_table *table = NULL;
>> >>> - const u8 *elf_data = (void *)ehdr;
>> >>> + const u8 *elf_data = (void *)fw->data;
>> >>> + u8 class = fw_elf_get_class(fw);
>> >>> + size_t fw_size = fw->size;
>> >>> + const void *ehdr = elf_data;
>> >>> + u16 shnum = elf_hdr_e_shnum(class, ehdr);
>> >>> + u32 elf_shdr_size = elf_size_of_shdr(class);
>> >>> + u16 shstrndx = elf_hdr_e_shstrndx(class, ehdr);
>> >>>
>> >>> /* look for the resource table and handle it */
>> >>> - shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff);
>> >>> - name_table = elf_data + shdr[ehdr->e_shstrndx].sh_offset;
>> >>> -
>> >>> - for (i = 0; i < ehdr->e_shnum; i++, shdr++) {
>> >>> - u32 size = shdr->sh_size;
>> >>> - u32 offset = shdr->sh_offset;
>> >>> -
>> >>> - if (strcmp(name_table + shdr->sh_name, ".resource_table"))
>> >>> + /* First, get the section header according to the elf class */
>> >>> + shdr = elf_data + elf_hdr_e_shoff(class, ehdr);
>> >>> + /* Compute name table section header entry in shdr array */
>> >>> + name_table_shdr = shdr + (shstrndx * elf_shdr_size);
>> >>> + /* Finally, compute the name table section address in elf */
>> >>> + name_table = elf_data + elf_shdr_sh_offset(class, name_table_shdr);
>> >>> +
>> >>> + for (i = 0; i < shnum; i++, shdr += elf_shdr_size) {
>> >>> + u64 size = elf_shdr_sh_size(class, shdr);
>> >>> + u64 offset = elf_shdr_sh_offset(class, shdr);
>> >>> + u32 name = elf_shdr_sh_name(class, shdr);
>> >>> +
>> >>> + if (strcmp(name_table + name, ".resource_table"))
>> >>> continue;
>> >>>
>> >>> table = (struct resource_table *)(elf_data + offset);
>> >>> @@ -270,21 +305,21 @@ find_table(struct device *dev, struct elf32_hdr *ehdr,
>> >>> size_t fw_size)
>> >>> */
>> >>> int rproc_elf_load_rsc_table(struct rproc *rproc, const struct firmware *fw)
>> >>> {
>> >>> - struct elf32_hdr *ehdr;
>> >>> - struct elf32_shdr *shdr;
>> >>> + const void *shdr;
>> >>> struct device *dev = &rproc->dev;
>> >>> struct resource_table *table = NULL;
>> >>> const u8 *elf_data = fw->data;
>> >>> size_t tablesz;
>> >>> + u8 class = fw_elf_get_class(fw);
>> >>> + u64 sh_offset;
>> >>>
>> >>> - ehdr = (struct elf32_hdr *)elf_data;
>> >>> -
>> >>> - shdr = find_table(dev, ehdr, fw->size);
>> >>> + shdr = find_table(dev, fw);
>> >>> if (!shdr)
>> >>> return -EINVAL;
>> >>>
>> >>> - table = (struct resource_table *)(elf_data + shdr->sh_offset);
>> >>> - tablesz = shdr->sh_size;
>> >>> + sh_offset = elf_shdr_sh_offset(class, shdr);
>> >>> + table = (struct resource_table *)(elf_data + sh_offset);
>> >>> + tablesz = elf_shdr_sh_size(class, shdr);
>> >>>
>> >>> /*
>> >>> * Create a copy of the resource table. When a virtio device starts
>> >>> @@ -317,13 +352,17 @@ EXPORT_SYMBOL(rproc_elf_load_rsc_table);
>> >>> struct resource_table *rproc_elf_find_loaded_rsc_table(struct rproc *rproc,
>> >>> const struct firmware *fw)
>> >>> {
>> >>> - struct elf32_hdr *ehdr = (struct elf32_hdr *)fw->data;
>> >>> - struct elf32_shdr *shdr;
>> >>> + const void *shdr;
>> >>> + u64 sh_addr, sh_size;
>> >>> + u8 class = fw_elf_get_class(fw);
>> >>>
>> >>> - shdr = find_table(&rproc->dev, ehdr, fw->size);
>> >>> + shdr = find_table(&rproc->dev, fw);
>> >>> if (!shdr)
>> >>> return NULL;
>> >>>
>> >>> - return rproc_da_to_va(rproc, shdr->sh_addr, shdr->sh_size);
>> >>> + sh_addr = elf_shdr_sh_addr(class, shdr);
>> >>> + sh_size = elf_shdr_sh_size(class, shdr);
>> >>> +
>> >>> + return rproc_da_to_va(rproc, sh_addr, sh_size);
>> >>> }
>> >>> EXPORT_SYMBOL(rproc_elf_find_loaded_rsc_table);
>> >>> diff --git a/drivers/remoteproc/remoteproc_elf_loader.h
>> >>> b/drivers/remoteproc/remoteproc_elf_loader.h
>> >>> new file mode 100644
>> >>> index 000000000000..fac3565734f9
>> >>> --- /dev/null
>> >>> +++ b/drivers/remoteproc/remoteproc_elf_loader.h
>> >>> @@ -0,0 +1,69 @@
>> >>> +/* SPDX-License-Identifier: GPL-2.0 */
>> >>> +/*
>> >>> + * Remote processor elf loader defines
>> >>> + *
>> >>> + * Copyright (C) 2019 Kalray, Inc.
>> >>> + */
>> >>> +
>> >>> +#ifndef REMOTEPROC_ELF_LOADER_H
>> >>> +#define REMOTEPROC_ELF_LOADER_H
>> >>> +
>> >>> +#include <linux/elf.h>
>> >>> +#include <linux/types.h>
>> >>> +
>> >>> +/**
>> >>> + * fw_elf_get_class - Get elf class
>> >>> + * @fw: the ELF firmware image
>> >>> + *
>> >>> + * Note that we use and elf32_hdr to access the class since the start of the
>> >>> + * struct is the same for both elf class
>> >>> + *
>> >>> + * Return: elf class of the firmware
>> >>> + */
>> >>> +static inline u8 fw_elf_get_class(const struct firmware *fw)
>> >>> +{
>> >>> + struct elf32_hdr *ehdr = (struct elf32_hdr *)fw->data;
>> >>> +
>> >>> + return ehdr->e_ident[EI_CLASS];
>> >>> +}
>> >>> +
>> >>> +#define ELF_GET_FIELD(__s, __field, __type) \
>> >>> +static inline __type elf_##__s##_##__field(u8 class, const void *arg) \
>> >>> +{ \
>> >>> + if (class == ELFCLASS32) \
>> >>> + return (__type) ((const struct elf32_##__s *) arg)->__field; \
>> >>> + else \
>> >>> + return (__type) ((const struct elf64_##__s *) arg)->__field; \
>> >>> +}
>> >>> +
>> >>> +ELF_GET_FIELD(hdr, e_entry, u64)
>> >>> +ELF_GET_FIELD(hdr, e_phnum, u16)
>> >>> +ELF_GET_FIELD(hdr, e_shnum, u16)
>> >>> +ELF_GET_FIELD(hdr, e_phoff, u64)
>> >>> +ELF_GET_FIELD(hdr, e_shoff, u64)
>> >>> +ELF_GET_FIELD(hdr, e_shstrndx, u16)
>> >>> +
>> >>> +ELF_GET_FIELD(phdr, p_paddr, u64)
>> >>> +ELF_GET_FIELD(phdr, p_filesz, u64)
>> >>> +ELF_GET_FIELD(phdr, p_memsz, u64)
>> >>> +ELF_GET_FIELD(phdr, p_type, u32)
>> >>> +ELF_GET_FIELD(phdr, p_offset, u64)
>> >>> +
>> >>> +ELF_GET_FIELD(shdr, sh_size, u64)
>> >>> +ELF_GET_FIELD(shdr, sh_offset, u64)
>> >>> +ELF_GET_FIELD(shdr, sh_name, u32)
>> >>> +ELF_GET_FIELD(shdr, sh_addr, u64)
>> >>> +
>> >>> +#define ELF_STRUCT_SIZE(__s) \
>> >>> +static inline unsigned long elf_size_of_##__s(u8 class) \
>> >>> +{ \
>> >>> + if (class == ELFCLASS32)\
>> >>> + return sizeof(struct elf32_##__s); \
>> >>> + else \
>> >>> + return sizeof(struct elf64_##__s); \
>> >>> +}
>> >>> +
>> >>> +ELF_STRUCT_SIZE(shdr)
>> >>> +ELF_STRUCT_SIZE(phdr)
>> >>> +
>> >>> +#endif /* REMOTEPROC_ELF_LOADER_H */
>> >>> diff --git a/drivers/remoteproc/remoteproc_internal.h
>> >>> b/drivers/remoteproc/remoteproc_internal.h
>> >>> index 004867061721..eeb26434220e 100644
>> >>> --- a/drivers/remoteproc/remoteproc_internal.h
>> >>> +++ b/drivers/remoteproc/remoteproc_internal.h
>> >>> @@ -55,7 +55,7 @@ phys_addr_t rproc_va_to_pa(void *cpu_addr);
>> >>> int rproc_trigger_recovery(struct rproc *rproc);
>> >>>
>> >>> int rproc_elf_sanity_check(struct rproc *rproc, const struct firmware *fw);
>> >>> -u32 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw);
>> >>> +u64 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw);
>> >>> int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw);
>> >>> int rproc_elf_load_rsc_table(struct rproc *rproc, const struct firmware *fw);
>> >>> struct resource_table *rproc_elf_find_loaded_rsc_table(struct rproc *rproc,
>> >>> diff --git a/drivers/remoteproc/st_remoteproc.c
>> >>> b/drivers/remoteproc/st_remoteproc.c
>> >>> index ee13d23b43a9..a3268d95a50e 100644
>> >>> --- a/drivers/remoteproc/st_remoteproc.c
>> >>> +++ b/drivers/remoteproc/st_remoteproc.c
>> >>> @@ -190,7 +190,7 @@ static int st_rproc_start(struct rproc *rproc)
>> >>> }
>> >>> }
>> >>>
>> >>> - dev_info(&rproc->dev, "Started from 0x%x\n", rproc->bootaddr);
>> >>> + dev_info(&rproc->dev, "Started from 0x%llx\n", rproc->bootaddr);
>> >>>
>> >>> return 0;
>> >>>
>> >>> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
>> >>> index f84bd5fe0211..82cebca9344c 100644
>> >>> --- a/include/linux/remoteproc.h
>> >>> +++ b/include/linux/remoteproc.h
>> >>> @@ -382,7 +382,7 @@ struct rproc_ops {
>> >>> struct rproc *rproc, const struct firmware *fw);
>> >>> int (*load)(struct rproc *rproc, const struct firmware *fw);
>> >>> int (*sanity_check)(struct rproc *rproc, const struct firmware *fw);
>> >>> - u32 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw);
>> >>> + u64 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw);
>> >>> };
>> >>>
>> >>> /**
>> >>> @@ -498,7 +498,7 @@ struct rproc {
>> >>> int num_traces;
>> >>> struct list_head carveouts;
>> >>> struct list_head mappings;
>> >>> - u32 bootaddr;
>> >>> + u64 bootaddr;
>> >>
>> >> That will cause problems for rproc_coredump()[1] and fixing it properly
>> >> likely means that a 32 or 64 elf should be generated based on the type of image
>> >> that was loaded. This is also true if ->p_vaddr and ->p_paddr (also in the same
>> >> function) are to be handled properly.
>> >>
>> >> I'm interested in your opinion on this.
>> >
>> > Indeed, you are right !
>> >
>> > I'm "afraid" I will have to fix that !
>> > Most sane thing to do is to dump an elf with the input elf class.
>> > I will make a V4 with a patch for that.
>> >
>>
>> Actually, this does not seems directly related to elf loading.
>> The coredump mecanism dumps segment that have been registered
>> using rproc_coredump_add_*_segment and this is not done directly
>> by the elf loader.
>
> Correct, but it is fair to assume rpoc_coredump_add_*_segment() is called for
> the image that will run on the MCU (otherwiser doing so would be pointless).
>
>> I'm not 100% sure but the coredump elf format is not tied to
>> any machine (EM_NONE) and as a special type (ET_CORE) so the elf
>> type is probably not relevant adn elf64 would be generic.
>
> That is true, we could generate an elf64 core dump for both 32 and 64 bit MCU
> image and be done with it. But that is almost guaranteed to break some user
> space that isn't tailored to deal with an elf64.
>
>> If some coredump user could speak for that part, that would be
>> nice !
>>
>> If needed, then we could add a rproc_coredump_set_format() function
>> to specify various parameters (machine, elf type, lsb/msb, etc).
>>
>
> For this specific patchset I don't think you need to cover cases where this much
> flexibility is needed (up to now it hasn't been a requiment).
>
> Keeping track of the type of image being loaded in something like
> rproc::elfclass and use that information to generate the right elf core in
> rproc_coredump() is probably sufficient for the time being.

Ok, let's go this way.

>
>> Let me know what you think about it.
>>
>> Clément
>>
>> > Thanks,
>> >
>> > Clément
>> >
>> >>
>> >> Thanks,
>> >> Mathieu
>> >>
>> >> [1].
>> >> https://elixir.bootlin.com/linux/latest/source/drivers/remoteproc/remoteproc_core.c#L1600
>> >>
>> >>> struct list_head rvdevs;
>> >>> struct list_head subdevs;
>> >>> struct idr notifyids;
>> >>> --
> > > >> 2.15.0.276.g89ea799