Additionally HPi is not a mistake, corporate requires that we refer to ourselves as Hewlett Packard Inc since the split in 2015. I will perhaps update this to be the full name for clarity.
From: McMillan, Erich Sent: Friday, September 25, 2020 12:15 PM To: Laszlo Ersek <ler...@redhat.com>; qemu-devel@nongnu.org Cc: dgilb...@redhat.com; m...@redhat.com; marcel.apfelb...@gmail.com; imamm...@redhat.com; kra...@redhat.com Subject: RE: [PATCH v5] hw/i386/pc: add max combined fw size as machine configuration option Hi Laszlo, Thank you for the feedback, apologies that I missed the exact line references I was moving too fast. I appreciate you taking the time to explain the nuances. On an unrelated note, it seems that my patches are no longer appearing in https://lists.nongnu.org/archive/html/qemu-devel/2020-09/index.html is this because I need to cc qemu-devel@nongnu.org<mailto:qemu-devel@nongnu.org> rather than –to? -Erich From: Laszlo Ersek [mailto:ler...@redhat.com] Sent: Friday, September 25, 2020 2:00 AM To: McMillan, Erich <erich.mcmil...@hp.com<mailto:erich.mcmil...@hp.com>>; qemu-devel@nongnu.org<mailto:qemu-devel@nongnu.org> Cc: dgilb...@redhat.com<mailto:dgilb...@redhat.com>; m...@redhat.com<mailto:m...@redhat.com>; marcel.apfelb...@gmail.com<mailto:marcel.apfelb...@gmail.com>; imamm...@redhat.com<mailto:imamm...@redhat.com>; kra...@redhat.com<mailto:kra...@redhat.com> Subject: Re: [PATCH v5] hw/i386/pc: add max combined fw size as machine configuration option Hi Erich, when processing review feedback, please pay attention to *where* the review comments are inserted, in response to your patch email. I'm pointing this out not because I want to annoy you with my obsessions, but because I consider this discussion a kind of "git + mailing lists" training for you. (In accordance with your first message on the topic.) Please see specifics below: On 09/25/20 05:36, Erich Mcmillan wrote: > From: Erich McMillan <erich.mcmil...@hp.com<mailto:erich.mcmil...@hp.com>> > > At HPi we have a need for increased fw size to enable testing of our custom > fw. > > Signed-off-by: Erich McMillan > <erich.mcmil...@hp.com<mailto:erich.mcmil...@hp.com>> > > Change since v4: > Add explicit return to pc_machine_set_max_fw_size. > Remove /* default */ from max_fw_size initialization. > --- > > hw/i386/pc.c | 52 ++++++++++++++++++++++++++++++++++++++++++++ > hw/i386/pc_sysfw.c | 13 ++--------- > include/hw/i386/pc.h | 2 ++ > 3 files changed, 56 insertions(+), 11 deletions(-) Please refer to my earlier feedback, archived at the following location: 8fdbf9f1-5125-1c39-4ec7-f99f017d4345@redhat.com">http://mid.mail-archive.com/8fdbf9f1-5125-1c39-4ec7-f99f017d4345@redhat.com<8fdbf9f1-5125-1c39-4ec7-f99f017d4345@redhat.com">http://mid.mail-archive.com/8fdbf9f1-5125-1c39-4ec7-f99f017d4345@redhat.com> As I say in that message, the v(n)->v(n+1) changelog belongs 'between the "---" separator and the diffstat'. In that message, I marked the specific location with [*]. Basically the "---" separator terminates the commit message, and the first "diff --git" line starts the code changes. What's between them is thrown away, when the patch is applied. So in that throwaway area, git-format-patch places the diffstat automatically (because it gives reviewers a helpful overview of the patch, but is not useful for patch application). And that's also the area where the v(n)->v(n+1) changelog should be included. Traditionally, we place that log above the diffstat. > > diff --git a/hw/i386/pc.c b/hw/i386/pc.c > index d11daacc23..6e66cbbc41 100644 > --- a/hw/i386/pc.c > +++ b/hw/i386/pc.c > @@ -1869,6 +1869,51 @@ static void pc_machine_set_max_ram_below_4g(Object > *obj, Visitor *v, > pcms->max_ram_below_4g = value; > } > > +static void pc_machine_get_max_fw_size(Object *obj, Visitor *v, > + const char *name, void *opaque, > + Error **errp) > +{ > + PCMachineState *pcms = PC_MACHINE(obj); > + uint64_t value = pcms->max_fw_size; > + > + visit_type_size(v, name, &value, errp); > +} > + > +static void pc_machine_set_max_fw_size(Object *obj, Visitor *v, > + const char *name, void *opaque, > + Error **errp) > +{ > + PCMachineState *pcms = PC_MACHINE(obj); > + Error *error = NULL; > + uint64_t value; > + > + visit_type_size(v, name, &value, &error); > + if (error) { > + error_propagate(errp, error); > + return; > + } > + > + /* > + * We don't have a theoretically justifiable exact lower bound on the base > + * address of any flash mapping. In practice, the IO-APIC MMIO range is > + * [0xFEE00000..0xFEE01000] -- see IO_APIC_DEFAULT_ADDRESS --, leaving free > + * only 18MB-4KB below 4G. For now, restrict the cumulative mapping to 8MB in > + * size. > + */ > + if (value > 16 * MiB) { > + error_setg(errp, > + "User specified max allowed firmware size %" PRIu64 " is " > + "greater than 16MiB. If combined firwmare size exceeds " > + "16MiB the system may not boot, or experience intermittent" > + "stability issues.", > + value); > + } > + > + pcms->max_fw_size = value; > + > + return; > +} This return statement is useless. Please see my review at: de343c71-f446-c68b-d0bc-5f9db97b5a00@redhat.com">http://mid.mail-archive.com/de343c71-f446-c68b-d0bc-5f9db97b5a00@redhat.com<de343c71-f446-c68b-d0bc-5f9db97b5a00@redhat.com">http://mid.mail-archive.com/de343c71-f446-c68b-d0bc-5f9db97b5a00@redhat.com> There I wrote, 'Please put a "return" statement here'. And, my request was placed *exactly between* the error_setg() call and the closing brace. The idea being that, if we take the (value > 16 * MiB) branch, then yes we need to set the error, but we also need to abandon the rest of the function. If "value" is invalid (out of bounds), then "pcms->max_fw_size = value" is exactly the assignment that we do *not* want to reach. > + > static void pc_machine_initfn(Object *obj) > { > PCMachineState *pcms = PC_MACHINE(obj); > @@ -1884,6 +1929,7 @@ static void pc_machine_initfn(Object *obj) > pcms->smbus_enabled = true; > pcms->sata_enabled = true; > pcms->pit_enabled = true; > + pcms->max_fw_size = 8 * MiB; Thank you for dropping the comment. Summary: - the changelog is helpful (thanks!), it's placement is not perfect yet - the return statement should be moved so that it terminate the (value > 16 * MiB) branch. Also, I think "HPi" (rather than "HP") in the commit message *could* be a typo (I'm not sure). Thanks, Laszlo > > pc_system_flash_create(pcms); > pcms->pcspk = isa_new(TYPE_PC_SPEAKER); > @@ -2004,6 +2050,12 @@ static void pc_machine_class_init(ObjectClass *oc, > void *data) > > object_class_property_add_bool(oc, PC_MACHINE_PIT, > pc_machine_get_pit, pc_machine_set_pit); > + > + object_class_property_add(oc, PC_MACHINE_MAX_FW_SIZE, "size", > + pc_machine_get_max_fw_size, pc_machine_set_max_fw_size, > + NULL, NULL); > + object_class_property_set_description(oc, PC_MACHINE_MAX_FW_SIZE, > + "Maximum combined firmware size"); > } > > static const TypeInfo pc_machine_info = { > diff --git a/hw/i386/pc_sysfw.c b/hw/i386/pc_sysfw.c > index b6c0822fe3..22450ba0ef 100644 > --- a/hw/i386/pc_sysfw.c > +++ b/hw/i386/pc_sysfw.c > @@ -39,15 +39,6 @@ > #include "hw/block/flash.h" > #include "sysemu/kvm.h" > > -/* > - * We don't have a theoretically justifiable exact lower bound on the base > - * address of any flash mapping. In practice, the IO-APIC MMIO range is > - * [0xFEE00000..0xFEE01000] -- see IO_APIC_DEFAULT_ADDRESS --, leaving free > - * only 18MB-4KB below 4G. For now, restrict the cumulative mapping to 8MB in > - * size. > - */ > -#define FLASH_SIZE_LIMIT (8 * MiB) > - > #define FLASH_SECTOR_SIZE 4096 > > static void pc_isa_bios_init(MemoryRegion *rom_memory, > @@ -182,10 +173,10 @@ static void pc_system_flash_map(PCMachineState *pcms, > } > if ((hwaddr)size != size > || total_size > HWADDR_MAX - size > - || total_size + size > FLASH_SIZE_LIMIT) { > + || total_size + size > pcms->max_fw_size) { > error_report("combined size of system firmware exceeds " > "%" PRIu64 " bytes", > - FLASH_SIZE_LIMIT); > + pcms->max_fw_size); > exit(1); > } > > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h > index fe52e165b2..f7c8e7cbfe 100644 > --- a/include/hw/i386/pc.h > +++ b/include/hw/i386/pc.h > @@ -43,6 +43,7 @@ struct PCMachineState { > bool smbus_enabled; > bool sata_enabled; > bool pit_enabled; > + uint64_t max_fw_size; > > /* NUMA information: */ > uint64_t numa_nodes; > @@ -59,6 +60,7 @@ struct PCMachineState { > #define PC_MACHINE_SMBUS "smbus" > #define PC_MACHINE_SATA "sata" > #define PC_MACHINE_PIT "pit" > +#define PC_MACHINE_MAX_FW_SIZE "max-fw-size" > > /** > * PCMachineClass: >
