| Message ID | 93646ba2-ca84-755d-290b-d7470827ef46@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86/ACPI: correct off-by-1 in SGI MMCFG check | expand |
On Mon, Jul 17, 2023 at 11:43:28AM +0200, Jan Beulich wrote: > As supported by the printk() (deliberately made visible in context by > also correcting a mis-indented return statement), "above 4GiB" is meant > here. Avoid comparison with a constant to "escape" Misra rule 7.2 > complaints. (Note however that even up-to-date Linux, which is where we > "inherited" this code from, still uses the very same off-by-1 check.) > > Fixes: 94ea0622c5b8 ("x86-64/mmcfg: relax base address restriction") > Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Albeit I wonder how relevant those checks are anymore, TBH I would be quite tempted to just drop all this. Thanks, Roger.
--- a/xen/arch/x86/x86_64/acpi_mmcfg.c +++ b/xen/arch/x86/x86_64/acpi_mmcfg.c @@ -50,7 +50,7 @@ static int __init acpi_mcfg_check_entry( { int year; - if (cfg->address < 0xFFFFFFFF) + if (cfg->address == (uint32_t)cfg->address) return 0; if (!strncmp(mcfg->header.oem_id, "SGI", 3)) @@ -59,7 +59,7 @@ static int __init acpi_mcfg_check_entry( if (mcfg->header.revision >= 1 && dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year >= 2010) - return 0; + return 0; printk(KERN_ERR "MCFG region for %04x:%02x-%02x at %#"PRIx64 " (above 4GB) ignored\n",
As supported by the printk() (deliberately made visible in context by also correcting a mis-indented return statement), "above 4GiB" is meant here. Avoid comparison with a constant to "escape" Misra rule 7.2 complaints. (Note however that even up-to-date Linux, which is where we "inherited" this code from, still uses the very same off-by-1 check.) Fixes: 94ea0622c5b8 ("x86-64/mmcfg: relax base address restriction") Signed-off-by: Jan Beulich <jbeulich@suse.com>