165 lines
6.3 KiB
Diff
165 lines
6.3 KiB
Diff
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From 2f2265a8cbc6b43deb169c525204ea7df02e9363 Mon Sep 17 00:00:00 2001
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From: Hans de Goede <hdegoede@redhat.com>
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Date: Mon, 9 Mar 2020 13:55:02 +0100
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Subject: [PATCH 1/2] iommu/vt-d: dmar: replace WARN_TAINT with pr_warn +
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add_taint
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Quoting from the comment describing the WARN functions in
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include/asm-generic/bug.h:
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* WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
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* significant kernel issues that need prompt attention if they should ever
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* appear at runtime.
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*
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* Do not use these macros when checking for invalid external inputs
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The (buggy) firmware tables which the dmar code was calling WARN_TAINT
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for really are invalid external inputs. They are not under the kernel's
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control and the issues in them cannot be fixed by a kernel update.
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So logging a backtrace, which invites bug reports to be filed about this,
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is not helpful.
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Some distros, e.g. Fedora, have tools watching for the kernel backtraces
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logged by the WARN macros and offer the user an option to file a bug for
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this when these are encountered. The WARN_TAINT in warn_invalid_dmar()
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+ another iommu WARN_TAINT, addressed in another patch, have lead to over
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a 100 bugs being filed this way.
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This commit replaces the WARN_TAINT("...") calls, with
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pr_warn(FW_BUG "...") + add_taint(TAINT_FIRMWARE_WORKAROUND, ...) calls
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avoiding the backtrace and thus also avoiding bug-reports being filed
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about this against the kernel.
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BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1564895
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Fixes: e625b4a95d50 ("iommu/vt-d: Parse ANDD records")
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Fixes: fd0c8894893c ("intel-iommu: Set a more specific taint flag for invalid BI
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Cc: stable@vger.kernel.org
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Signed-off-by: Hans de Goede <hdegoede@redhat.com>
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---
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drivers/iommu/dmar.c | 11 ++++++-----
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1 file changed, 6 insertions(+), 5 deletions(-)
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diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
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index 071bb42bbbc5..87194a46cb0b 100644
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--- a/drivers/iommu/dmar.c
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+++ b/drivers/iommu/dmar.c
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@@ -440,12 +440,13 @@ static int __init dmar_parse_one_andd(struct acpi_dmar_header *header,
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/* Check for NUL termination within the designated length */
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if (strnlen(andd->device_name, header->length - 8) == header->length - 8) {
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- WARN_TAINT(1, TAINT_FIRMWARE_WORKAROUND,
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+ pr_warn(FW_BUG
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"Your BIOS is broken; ANDD object name is not NUL-terminated\n"
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"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
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dmi_get_system_info(DMI_BIOS_VENDOR),
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dmi_get_system_info(DMI_BIOS_VERSION),
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dmi_get_system_info(DMI_PRODUCT_VERSION));
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+ add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
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return -EINVAL;
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}
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pr_info("ANDD device: %x name: %s\n", andd->device_number,
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@@ -471,14 +472,14 @@ static int dmar_parse_one_rhsa(struct acpi_dmar_header *header, void *arg)
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return 0;
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}
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}
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- WARN_TAINT(
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- 1, TAINT_FIRMWARE_WORKAROUND,
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+ pr_warn(FW_BUG
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"Your BIOS is broken; RHSA refers to non-existent DMAR unit at %llx\n"
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"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
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drhd->reg_base_addr,
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dmi_get_system_info(DMI_BIOS_VENDOR),
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dmi_get_system_info(DMI_BIOS_VERSION),
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dmi_get_system_info(DMI_PRODUCT_VERSION));
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+ add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
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return 0;
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}
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@@ -827,14 +828,14 @@ int __init dmar_table_init(void)
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static void warn_invalid_dmar(u64 addr, const char *message)
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{
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- WARN_TAINT_ONCE(
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- 1, TAINT_FIRMWARE_WORKAROUND,
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+ pr_warn_once(FW_BUG
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"Your BIOS is broken; DMAR reported at address %llx%s!\n"
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"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
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addr, message,
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dmi_get_system_info(DMI_BIOS_VENDOR),
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dmi_get_system_info(DMI_BIOS_VERSION),
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dmi_get_system_info(DMI_PRODUCT_VERSION));
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+ add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
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}
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static int __ref
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--
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2.25.1
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From 038ebd8952c5fb3ba3b5e09b0b55a4e617ae22bf Mon Sep 17 00:00:00 2001
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From: Hans de Goede <hdegoede@redhat.com>
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Date: Mon, 9 Mar 2020 14:12:37 +0100
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Subject: [PATCH 2/2] iommu/vt-d: dmar_parse_one_rmrr: replace WARN_TAINT with
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pr_warn + add_taint
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Quoting from the comment describing the WARN functions in
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include/asm-generic/bug.h:
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* WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
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* significant kernel issues that need prompt attention if they should ever
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* appear at runtime.
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*
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* Do not use these macros when checking for invalid external inputs
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The (buggy) firmware tables which the dmar code was calling WARN_TAINT
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for really are invalid external inputs. They are not under the kernel's
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control and the issues in them cannot be fixed by a kernel update.
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So logging a backtrace, which invites bug reports to be filed about this,
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is not helpful.
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Some distros, e.g. Fedora, have tools watching for the kernel backtraces
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logged by the WARN macros and offer the user an option to file a bug for
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this when these are encountered. The WARN_TAINT in dmar_parse_one_rmrr
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+ another iommu WARN_TAINT, addressed in another patch, have lead to over
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a 100 bugs being filed this way.
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This commit replaces the WARN_TAINT("...") call, with a
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pr_warn(FW_BUG "...") + add_taint(TAINT_FIRMWARE_WORKAROUND, ...) call
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avoiding the backtrace and thus also avoiding bug-reports being filed
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about this against the kernel.
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BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1808874
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Fixes: f5a68bb0752e ("iommu/vt-d: Mark firmware tainted if RMRR fails sanity check")
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Cc: Barret Rhoden <brho@google.com>
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Cc: stable@vger.kernel.org
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Signed-off-by: Hans de Goede <hdegoede@redhat.com>
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---
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drivers/iommu/intel-iommu.c | 6 ++++--
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1 file changed, 4 insertions(+), 2 deletions(-)
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diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
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index 6fa6de2b6ad5..3857a5cd1a75 100644
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--- a/drivers/iommu/intel-iommu.c
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+++ b/drivers/iommu/intel-iommu.c
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@@ -4460,14 +4460,16 @@ int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg)
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struct dmar_rmrr_unit *rmrru;
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rmrr = (struct acpi_dmar_reserved_memory *)header;
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- if (rmrr_sanity_check(rmrr))
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- WARN_TAINT(1, TAINT_FIRMWARE_WORKAROUND,
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+ if (rmrr_sanity_check(rmrr)) {
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+ pr_warn(FW_BUG
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"Your BIOS is broken; bad RMRR [%#018Lx-%#018Lx]\n"
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"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
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rmrr->base_address, rmrr->end_address,
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dmi_get_system_info(DMI_BIOS_VENDOR),
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dmi_get_system_info(DMI_BIOS_VERSION),
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dmi_get_system_info(DMI_PRODUCT_VERSION));
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+ add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
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+ }
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rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
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if (!rmrru)
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--
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2.25.1
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